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Northern
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A SYMPOSIUM
The editors:
CHARLES W. SLAUGHTER, Research Hydrologist
U.S. Army Cold Regions Research
and Engineering Laboratory
Fairbanks, Alaska 99701
RICHARD J. BARNEY, Principal Fire Control Scientist
U.S. Forest Service Forestry Sciences Laboratory
College, Alaska 99701
GEORGE M. HANSEN, Supervisory Editor
U.S. Forest Service, Pacific Northwest Forest
and Range Experiment Station
Portland, Oregon 97208
Proprietary or brand names are used only to document
actual experience; their use does not imply approval of the
product to the exclusion of others which may also be suitable.
Cover photos: Fire crowning in spruce near Kenai in the Swanson River area.
Wildfire in the vast roadless taiga.
ARLIS
Alaska Resources
Library & Information Services
Anch(),.~~,. Alaska
Fire in the
Northern
Environment-
A Symposium
ARLIS
Edited by
C. W. Slaughter
Richard J. Barney
G. M. Hansen
Alaska Resources
Library & Information SerVices
Anchorage, Alaska
Published in 1971 by
Pacific Northwest Forest and Range Experiment Station
Forest Service, U.S. Department of Agriculture
Portland, Oregon
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1911
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Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
(!}Preface
A symposium on Fire in the Northern Environment was held April 13th
and 14th, 1971, at the University of Alaska, College, Alaska. The symposium
was sponsored by the Alaska Forest Fire Council and the Alaska Section,
Society of American Foresters.
The Alaska Forest Fire Council (AFFCO) was formally established on
April 3, 1969, with the primary objective being "to provide a forum to
coordinate and promote activities related to wildland fires and their effects."
Early in 1970 the idea arose that a symposium be organized to discuss
wildfire in interior Alaska. Such a meeting would provide an opportunity to
explore the current state of knowledge of wildfire and its interrelations in
the Alaskan environment. The outcome could serve as a basis for future
recommendations on needed areas of research in this broad field. Following
the initial decision to hold this meeting, the Alaska Section, Society of
American Foresters,joined with AFFCO to provide moral and financial sup-
. port for the symposium.
The purpose of this symposium was to explore some aspects of wildfire in
the subarctic. We hoped to 'delineate and clarify many of the current ques-
tions and opinions on wildfire in the subarctic-its relationship to the natural
environment and to man's use of that environment-as well as to consider
some aspects of fire control in this region. Participation was solicited from
all persons having an interest in the subject-researchers, recreationists,
natural resource managers, and private citizens were welcomed. Opportuni-
ties were provided to ask questions, air individual viewpoints, and develop ,
given topics in greater depth.
The symposium opened Tuesday, April 13th, with a welcome from Dr. E.
H. Beistline, Provost, University of Alaska. Additional introductions were
made by Dr. C. W. Slaughter, Symposium Chairman, and Mr. A. L. Comiskey,
current AFFCO president. Immediately following Dr. E. V. Komarek's stim-
ulating keynote address, attention turned to presentation of formal papers
and discussions. Technical sessions were competently led by session chair-
men: Dr. E. V. Komarek, Tall Timbers Research Station; Mr. A. M. Roberts,
General Counsel for the Western Forestry and Conservation Association; Mr.
R. C. Krumm, Fairbanks District Manager, U.S. Bureau of Land Manage-
ment; and Dr. F. C. Dean, College of Biological Sciences and Renewable
Resources, University of Alaska. More than 115 people were in attendance at
the opening session, and 97 individuals formally registered for the 2-day
symposium. The evening of April 13th a banquet was held at the Ft. Wain-
wright Officers' Open Mess. Mr. Jerry Zamber, U.S. Bureau of Land Manage-
ment, addressed the group on the subject of the proposed trans-Alaska oil
pipeline.
It would be presumptuous to imply that all topics relevant to subarctic
wildfire-environment relationships were even mentioned, let alone fully
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explored during these sessions. However, it is safe to state that this meeting
was a "first" in Alaska in attempting to draw together natural resource
managers, fire control specialists, scientists, and private citizens to explore
jointly some of the ramifications of wildfire, its control and role in the
subarctic.
The papers in these proceedings have been assembled in order of their
presentation at the conference. In addition to the formal papers, transcripts
of the panel discussions and the summary commentary of Dr. E. V. Komarek
are included.
0 Acknowledgments
On behalf of the Alaska Forest Fire Council and the Alaska Section,
Society of American Foresters, we wish to thank the speakers for their
contribution to these proceedings and all participants for making it a success-
ful meeting. Dr. Earl Beistline, Provost of the University of Alaska, and Dr.
Keith Mather, Director of the Geophysical Institute, University of Alaska,
were most courteous in providing their facilities and services for this meet-
ing. We would like to thank Dr. E. V. Komarek, Sr., of Tall Timbers Re-
search Station, for his assistance and support of the entire endeavor.
A special thanks is due to the clerical and technician staff of the Forestry
Sciences Laboratory, U.S. Forest Service, College, Alaska, and the Alaska
Field Station, USACRREL, for their untiring help in preparing for and
presenting this meeting. Personnel of the Fairbanks District, U.S. Bureau of
Land Management, provided invaluable transportation and logistics support
for out-of-town participants.
The editorial support of Mr. George M. Hansen, Pacific Northwest Forest
and Range Experiment Station, and his staff-particularly Mrs. Betty Bell-is
gratefully acknowledged.
Acknowledgment is due the Pacific Northwest Forest and Range Experi-
ment Station, Forest Service, U.S. Department of Agriculture for publishing
these proceedings. The Bureau of Land Management of the U.S. Department
of the Interior, the U.S. Army Cold Regions Research and Engineering
Laboratory, the Alaska Section, Society of American Foresters, and the
Alaska Forest Fire Council helped to defray costs.
Charles W. Slaughter
Symposium Chairman
Contents
KEYNOTE ADDRESS:
Principles of fire ecology and fire management in relation
to the Alaskan environment
Page
E. V. Komarek, Sr. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
FIRE IN THE NORTHERN ENVIRONMENT:
Erosion, soil properties, and revegetation following a
severe burn in the Colorado Rockies
W. D. Striffler and E. W. Mogren . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Effects of fire and fire control on soil and water relations
in northern forests-a preliminary review
Dwane J. Sykes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Effects of fire in the taiga on the environment
Frederick B. Lotspeich and Ernst W. Mueller . . . . . . . . . . . . . . . . . 45
Wildfires in Alaska-some historical and
projected effects and aspects
Richard J. Barney . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
The natural role of fire in northern conifer forests
Miron L. Heinselman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Fire in park management
Joseph E. Hoffman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
National Park Service fire policy in
National Parks and Monuments
Richard G. Prasil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Effects of forest fire smoke on tourism in
Mount McKinley National Park, Alaska
I van D. Miller . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
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Fire effects andrehabilitation methods-
Swanson-Russian Rivers fires
John B. Hakala, Robert K. Seemel,
Page
Robert A. Richey, and John E. Kurtz .......... , . . . . . . . . . . . . 87
Effects of fire and fire control methods in interior Alaska
Salvatore DeLeonardis ................................... 101
Catline rehabilitation and restoration
Roger Bolstad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 07
A short history of the fire weather service and the "Federal
Plan for a National Fire Weather Service"
Harry L. Swift ......................................... 117
A relation~hip between National Fire Danger Rating System
spread index and time-of-day in interior Alaska
Nonan V. Noste ......................................... 121
Bureau of Land Management computerized fire-danger
rating system
Albert L. Comiskey ..................................... 129
Weather modification-a fire control tool
William J. Douglas ..................................... 139
Background, practice, and potential of chemicals in
controlling wildfires
Avrom R. Randleman ................................... 159
Values protected in interior Alaska
J. H. Richardson ....................................... 173
White spruce stringers in a fire-patterned
landscape in interior Alaska
William A. Quirk and Dwane J. Sykes ....................... 179
Effects of some intensive forest management practices
on white spruce ecosystems in interior Alaska
Keith Van Cleve ....................................... 199
Fire, vegetation, soil, and barren-ground caribou
relations in northern Canada
George W. Scotter ..................................... 209
Natural regeneration of interior Alaska forests-seed,
seedbed, and vegetative reproduction considerations
Page
John C. Zasada ....................................... 231
FIRE AND RESOURCES IN THE SUBARCTIC-PANEL DISCUSSION:
Charles W. Slaughter-Introduction ........................... 249
Roger A. Sylvester ....................................... 249
Ross W. Wein ........................................... 251
Curtis V. McVee ......................................... 253
David R. Klein ........................................... 255
A SUMMATION OF "FIRE IN THE NORTHERN ENVIRONMENT"
AND A SUGGESTION FOR A COOPERATIVE ECOLOGICAL
EXPERIMENT STATION
E. V. Komarek, Sr ........................................ 257
SYMPOSIUM ATTENDANCE LIST ........................... 267
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KEYNOTE ADDRESS
by
E. V. Komarek, Sr.
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Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
Principles of fire ecology
and fire management in
relation to the Alaskan
• environment
Abstract
Fire ecology is discussed in relation to basic ecological processes; the
characteristics of the fire environment are reviewed. Lightning and lightning
storms are considered as the primary natural cause of fires in nature. The
nature of fire and its relationship to plants, animals, and soils are briefly
examined. The effects of fire in Alaska are mentioned in relation to its
occurrence before and after occupancy by early man, Eskimo, Indian, and
the European. Differences in viewpoint between fire management and fire
control are discussed. The need for fire management research in Alaska is
stressed in relation to the management of forest, wildlife, watershed, recrea-
tion, and urban lands.
Several separate incidents culminate in this privilege of speaking before
you on the principles of fire ecology and fire management in relation to the
Alaskan environment. At one time, I had been led to believe that fire had no
natural place in the boreal environment, even after a quarter of a century of
studies in fire ecology.
My personal contacts with the unique circumpolar boreal forest habitat
had been limited to only the southernmost outposts of this interesting com-
munity in Wisconsin (13), and in the Great Smoky Mountains of Tennessee
and North Carolina (23). However, study of small mammals by my wife and
me in southern Georgia and in northern Florida (some in what is now the
Tall Timbers Research Station) had impressed me of the consistent beneficial
effect that fires had on the habitats of certain small mammals as well as on
that of the bobwhite quail (Colinus virginianus) (33, 34). This in turn
created a nagging doubt that my ideas or opinions about fire and the boreal
forest were correct. As a final consequence, we set out to make field studies
in Canada and Alaska.
Our first stop at the district forester's office in Port Arthur will never be
forgotten because his remarks and those of his staff were to the effect that at
least 95 percent of the boreal forest of Canada had regenerated on burned
E. V. Komarek, Sr.
Tall Timbers
Research Station
Tallahassee, Florida
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land. This led us to travel into Alaska, covering nearly all of the existing
paved or gravel roads and camping in many diverse habitats. These visits, as
well as an in-depth literature survey, familiarized me with the extensive
literature on the Canadian boreal forest. Much of this literature, particularly
some 10 or 15 years ago, was not readily available in the lower 48 States. In
fact, apparently that which was available was not read even in Alaska, for at
my last stop here, which was at a Forest Experiment Station, I was told that
lightning frres occurred only rarely and were of no consequence in interior
Alaska which is contrary to what I had read. This then was my introduction
to the fire ecology and fire management problems in the Alaskan
environment.
The cooperation of the Canadian and the Yukon Territory Forest Services
is gratefully acknowledged. With their help, it was possible to see many
diverse habitats from Nova Scotia to British Columbia, including an over-
mature spruce forest some 300 years old.
When your symposium chairman, Dr. Slaughter, suggested that I present
the keynote address at this symposium I went quickly to a dictionary for a
definition of such a talk. I found, in essence, that a keynote address is a
speech, usually at a political gathering, that presents the principal issues in
which those present are interested. Understanding that you do have politics
in Alaska, in particular pertaining to a certain useful substance and not
wishing to get embroiled in that, for fire problems have sufficient heat by
themselves, 1 sought further enlightenment. I then discovered that
"keynote" meant that such a talk should be concerned with the basic or
ruling aspects. Therefore, I will limit myself to the principles of fire ecology
and the topic that fire management, to be successful, must be based on these
principles. Note, however, that I have used the words "fire management"
and not frre control, for the latter usually implies only fire exclusion.
Fire Ecology
Fire ecology is the scientific study of fire's effect on the environment, the
interrelationships of plants, and the animals that live in such habitats. The
principles of fire ecology are based on certain physical and biological laws.
These are discussed briefly here.
Conservation of matter and energy.-The planet earth is one small part of
the universe, but all of its processes follow the three laws of thermo-
dynamics. The frrst of these is the law of conservation of matter and energy
and is pertinent to this discussion. This simply means that neither matter nor
energy is ever destroyed but can only change its form. Burning by any
means, even by man, in reality destroys nothing; it is only a change of one
form of matter or energy to another. This, of course, comes as quite a shock
to those people who believe frres, as so often reported, destroy acres of
vegetation and land.
Major physical forces.-Two major physical forces are interrelated and also
must be considered in our attempt to understand the principles of fire
ecology: (1) fire or rapid oxidation, the changing of organic matter back to
its original components-water, C02 , and minerals-and (2) electricity as the
energy source needed to initiate rapid oxidation. The physical form of fire or
rapid oxidation is familiar. One of the most obvious physical features of
electricity is the lightning boJt, a function of the activity of the changing
electrical field of the earth, usually produced in connection with thunder-
storms. Because of this vast discharge of energy and the resulting heat at the
point of impact on the earth's surface, the temperature is raised well above
the kindling point of the plant material.
Basic ecological processes.-There are certain basic ecological processes
that must be considered in a discussion on fire ecology and fire management
because of the impact or effect of fire or fire exclusion. Time and space will
allow me only briefly to mention these processes, but they should be kept
constantly in mind in the following discussion. They are:
1. Change-Always there is change. This is fundamental. All living things
change by metabolic processes and by natural selection and
evolution.
2. Continuity-Species cannot live successfully as individuals but only
through reproduction. Individuals are born, they grow and
mature, and they die. Any species becomes extinct if the continu-
ity is broken.
3. Diversity-No two individuals, plants or animals, are exactly alike and
so no two species or communities can be exactly alike.
4. Succession-This is the more or less orderly pattern of events and
processes in nature whereby plant and animal species replace each
other as a result of a changing environment.
5. Competition-Living things must compete with each other for
nutrients, light, water, space, etc.
6. Cooperation -Plants and animals live together in an environment,
each to its niche, and frequently contribute to each other's
biological economy.
7. Metabolism -Waste results from metabolism, and death would soon
overwhelm the earth if there were no processes to change and
recycle such refuse. Waste must be changed to be removed
because no living thing can live in its own waste.
8. Adaptation -Living things must have a dwelling place, each with
specific environmental requirements.
The action of fire on these eight major ecological processes is exceedingly
diverse and extensive. Fire exclusion likewise has an important impact on all
of these. It is this great difference in effect, fire and/or fire exclusion, that
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gives the land manager a most important tool in the management of lands for
certain specific purposes.
Fire characteristics.-The place of fire in nature has been responsible for
discussions as heated as the raging crown fire in spruce stands and as obscure
and dense as the smoke from a deep-seated wet peat fire. Because of this, I
will have to point out some very elemental features which are so common-
place that they are rarely taken into consideration. The first of these is that
the heat of a fire is above the burning substance, not below it. The second,
one of the main reasons fire discussions have been so controversial, is that no
two fires are alike; they are like living things, they change constantly. Scien-
tific studies, otherwise of excellent quality and design, are usually conducted
without regard to the kind of fire that occurred-when or where it occurred
in relation to the life pattern of growing things; the kind, character, and
amount of fuel that fed the fire; and particularly, over how long a period fire
had been excluded either by man or by nature. Usually no history of the area
where the fire occurred and of man's possible disruption of natural conditions
is even considered, although it may be available.
Fire and the environment.-The impact of fire changes the relationships
between the plant and animal communities as well as between them and the
climate. Fire also confuses the interpretation of ecological research, creates
situations of apparent conflict, and torments the investigator because of the
extreme variation of fires and their dependence for effect on a great many
variable factors. Fire research, particularly, becomes difficult if related to
small, isolated, or specialized investigations.
The emphasis for the past century or so has centered on the forest; where-
as, this is only a very small part of the ecosystem as far as the total inter-
relation is concerned. Few animals, particularly vertebrate animals including
man, receive much from trees in the way of food during any 12-month
period. Without the tropical rain-forest animals, the list of mammals that
depend on trees is small indeed. In my opinion, the place of the forest in the
total ecosystem has been exaggerated, and it is time to consider just how
necessary it is as the natural environment or habitat of major ecosystems.
In all too many instances, we have tried to develop the most intricate and
sophisticated investigations instead of first trying to learn the general pattern
and then going into detailed studies. Permanent fixed points regularly photo-
graphed will not require a great deal of time, effort, or funds. Naturally
replicated plots of considerable size will yield still more data. In fact, I feel
that the greatest hazard in applying a fixed-point photographic study is that
it is too simple. However, the HSB-No. I computer can readily digest much
information from such a study if it is standardized and replicated enough
times. (The HSB-No. I computer is the Homo sapiens brain that thinks.)
Studies that are too localized do present difficulties when we try to learn
and discover ecological processes. This is particularly true in fire ecology.
Some studies remind me of an intensive investigation being made of a
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carburetor without any knowledge of the auto. This kind of study certainly
makes it difficult, if not impossible, for the investigator to relate the carbure-
tor to the process of propulsion,Jet alone acceleration, starting, and ignition.
Lightning storms.-! believe it is pertinent to discuss the thunderstorm in
some detail, for this natural mechanism is not just a local phenomenon. The
electrical discharges during thunderstorms have been considered by several
investigators to be a mechanism to assist in maintaining the balance of the
earth's electrical field (15, 17, 19, 20, 29, 36). The electrical field surround-
ing the earth is important ecologically, although in many respects still un-
known particularly in regard to its effect on living organisms.
All living organisms depend upon electrical processes essential to life.
Every single living cell is an electrical battery with a positive and a negative
charge. If the cell membrane is ruptured, the electrical potential of the cell is
discharged and the cell is no longer alive. Life, through chemical processes, is
electrical and is carried on in a medium that is also electrical-the electric
field. Ecologists and physiologists have long overlooked this vital aspect and
the role played by it in our atmosphere and climate. Surely, the electrical
field and electricity are as necessary to living things as are the other more
easily studied physical effects of the atmosphere and climate. Unfortunately,
electrical effects on living organisms are virtually unstudied. However, elec-
tricity during the thunderstorm has been investigated, but there is still much
to be learned.
The thunderstorm is extremely important to us in this symposium not
only because of lightning-started forest fires today, but also because of fires
ignited long before man had evolved. In a study of nature, one of the first
prerequisites is to attempt to discover and understand the interrelationships
of plants and animals and their environment before these were manipulated
by :man.
Fire is a natural environmental force, and it is particularly important to
learn what natural processes are involved because these usually cannot be
altered materially by man. Thunderstorms were, and are, a part of our
environment. Their frequency patterns have changed and will continue to
change as do other more easily observed climatic changes. Certainly, some-
thing that is as involved in the electrical balance of the earth's charge, as are
thunderstorms, is of considerable biological importance.
Schonland (29) wrote that the different electrical discharges on earth have
been recognized for about 100 years but that, until rather recently, "no
acceptable explanation could be offered for them," and that there had to be
"some charging process continually at work." Also:
... there are some 40,000 thunder-clouds in action over the whole
world every day and each of these acts as an electrical generator
floating between the earth and sky pumping electricity from one
to the other, and so maintaining negative and positive charges on
earth and upper air respectively in spite of contrary leakage cur-
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rent flowing in fine-weather regions. (Italics mine.)
Schonland (29) also emphasizes that because the earth is electrified,
" ... One of its rather striking consequences is that the charge in fine;.
weather regions should fluctuate with the total thunderstorm activity of the
world."
I ~~Y~ !!"..i:; ;.·~:j· !:;;i~; and generalized explanation has impressed upon you
that lightning, and the resulting thunderstorm, is one of the primary forces
on earth and that this activity was here from the beginning of the earth. It is
likely that life itself was formed by the action of lightning (26, 35).
Lightning and fire ecology.-Now, what evidence do we have that light-
ning does indeed ignite fires in nature, particularly in the northern environ-
ment? Fortunately, data have accumulated from many parts of the world
including Alaska; so today there can be no question that lightning has been,
and is, an important ecological factor (15, 16, 17, ). Although many writers
have mentioned lightning fires, usually very cursorily and briefly, in Canada
and Alaska it has been only relatively recently that quantitative and quali-
tative data have been available. These have been brought together in excel-
lent fashion by foresters, not ecologists in the usually biological sense. This
discipline, the science and profession of forestry, has made a tremendous,
although as yet unrecognized, contribution to this field.
Some of the very valuable papers about the northern environment should
be intensively studied by all that are interested in the ecology of the Alaskan
environment. For example, in 1960 Bennett published his "Survey of Light-
ning Fire Occurrences in Canada's Forests-1950-1959" (2), in which he
plotted nearly 10,000 lightning fires from Newfoundland to British
Columbia. In 1963, Hardy and Franks (11) reported extensively on both
lightning-(746) and man-caused (2,672) fires primarily in interior Alaska.
Requa (28) wrote on the lightning fire patterns in "Lightning behavior in the
Yukon." Recently, Barney (1) reported an extensive study on "Interior
Alaska Wildfires 195 6-1965." All of these investigators are ecologists as well
as foresters. ·
Their findings show a high incidence of fires in the northern environment,
except for the far northern barren-ground type of tundra. There appear to be
no records of lightning fires north of the Brooks Range in Alaska and in the
far northern reaches of Canada. Some meteorological evidence, which we do
not have time to discuss here, indicates lightning may be very infrequent or,
for long periods, not at all possible there. Because of time limits, we will
discuss primarily the interior of Alaska as delineated by Hardy and Franks
(11) and Barney (1).
From their investigations, we learn that in the period 1950-58, 546 or 24
percent of the recorded fires were by lightning, and these accounted for 76
percent of the burned-over acreage (11). And in the period from 1956 to
1965, 834 or 38 percent of the recorded fires were lightning caused and
accounted for 97 percent of the burned-over acreage (1 ). They agree on
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1957 as the peak year for lightning fires and that the lightning fire season is
from mid-May to September 1, whereas the man-caused fire season is from
March into October. The percentage of lightning fires, however, varied from
62 percent in 1959 to a low of 20 percent in 1965.
Hardy and Franks (11) published an interesting map of lightning fire
occurrence by isograms which shows that nearly all the fires occur in the
continental and transition climatological zones of Alaska. They point out,
however:
If complete detection coverage were possible, the lightning fire
isogram might appear considerably different. Over the past many
years, detection and reporting have been almost entirely by such
volunteers as airplane pilots, travelers, local residents, and miners.
We now know that many lightning fires occur in areas for which
the isogram indicates a low frequency. Some of these fires burn
large areas, and some may combine with other fires and appear as
only one for reporting purposef,;. Others burn and die out without
being reported. Many fires do not spread beyond a very small size,
and their existence is never known. Better detection and better -
reporting methods will no doubt change the pattern of the light-
ning fire isogram during the next few years.
Although man has been in Alaska only a relatively short time, he has made
some rather drastic changes in the environment, but he certainly has not
changed any basic ecological principles. He may have changed the effects of
these, accelerated them, or slowed th~m down; but they still continue.
The importance of lightning fires in interior Alaska is only too well known
to those who have to fight such fires. Unfortunately, this is not known by
either biological investigators or the general public. "
Nature of fire.-Let us examine this process we call fire more closely,
keeping these basic ecological "laws" in mind with the keen appreciation
that there is more there than meets the eye.
The flame and heat that we see from burning material, not only produces
light, but many other various radiations in many wavelengths. Unfortu-
nately, little is known about most of these, except perhaps infrared, and still
less is known of their· relationship to living things. However, we do have
evidence that some of these wavelengths are indeed important at least to
certain animals. Evans (8) has reported in detail about his investigations of
the fire beetles, a specie~ of the genus Melanophila, and the infrared sensory
pits on their hind legs. These remarkable insects can detect and locate forest
fires over long distances. They are attracted to the burning forest, and the
fire apparently triggers such reproductive processes as courtship and mating.
This was first observed by Poulton (2 7) in 1915, and recent studies have
proven their connections with infrared sensing organisms. These beetles are
found in Europe, Asia, United States, Canada, Mexico, and one species in
Central America. In North America, all 20 species are most abundant in the
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southern part, with two species in Alaska.
The relationships of animal behavior to fire is a fertile, pioneer field for
research. I have recently reviewed some of the interesting aspects of such
studies in "Fire and Animal Behavior" (21). Callahan (6, 7) has discussed the
many possible and fundamental relationships of such animals as insects to
various electrical wavelengths. He has also shown that they have many dif-
ferent organs to detect some of these and points out that there must be
many other unknown radiations. One cannot even conjecture as to the many
possible electrical radiations and phenomena that may be a vital part of our
atmosphere and climate.
We, like many other animals, feel some of these rays as heat. These are so
familiar that at times we do not relate some very obvious characteristics of
these to our studies and problems with fire. The fact that the greatest
amount of heat is above the burning material, not below it, is often forgot-
ten. We all know and practice this knowledge, that nearly all the heat is
greatest at the "cone" of the flame and that little is below the source. In
fact, the differences in temperature between the heat at the "cone" level in
relation to that below it are so great that the latter appear to be insignificant.
Wherever studies have been made, the soil is such a good insulator that very
little heat reaches below the surface levels, except when exceedingly heavy
accumulations of fuel develop and are ignited. Most of these types of fuel
accumulations are caused by man, and there is little relation of these to
either natural fires or controlled burning except in certain very exceptional
instances. For example, the wildfire that occurs following clearcutting tim-
ber operations is certainly not comparable in most respects to a natural fire.
Fire and plants.-Certain vegetations have evolved interesting adaptations
to the intense hea,t above the fire. Many species of pines, as well as some
other conifers, in many parts of the world have serotinous cones that require
heat to release the seed. Powells (1 0) writes in relation to the jack pine
(Pinus banksiana) that:
Heat from a heavy slash fire, with temperatures recorded at 1400
degrees at 1 foot above the ground to 600 degrees at 17 feet, is
sufficient to open all cones on a tree. The seeds in the cones are
uninjured by temperatures that do not cause actual cone ignition,
which is 60 seconds at 700 degrees to 2 seconds at 1300 degrees.
Cones exposed to temperatures of 900 degrees for 30 seconds had
high seed viability but those exposed for 60 seconds did not.
In the Alaskan environment, the black spruce (Picea mariana) has the
serotinous cone habit in varying degrees, and the cones can be blackened by
fire and still remain sound. The sand pine (Pinus clausa) that grows on
certain sterile white sand ridges along the Gulf of Mexico coast in northern
florida also has serotinous cones and likewise the lodgepole pine (Pinus
contorta) of the northern environment.
Another adaptation, generally recognized by foresters, is that many forest
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tree species in Alaska require mineral soil for best germination, seedling
survival, and growth. The two major species of conifers, black spruce (Picea
mariana) and white spruce (Picea glauca), have established forests on
burned-over land the breadth of a continent in its widest section. It should
be said, however, that repeated burning of these same forests will eliminate
seed trees and eventually the forest. We have, however, focused too much of
our attention in the past only on the trees. Trees are but a part, and in some
regions a very small part, of a rather complicated system of living things,
plants and animals, as well as minerals, water, and climate. The forest should
be considered, even if it is of the greatest economic importance in many
regions, as only part of a system, not the system itself.
Many plant species respond to fire and its effects in many other ways, too
many to begin to enumerate here. Many seeds of plants germinate more
readily and rapidly if slightly heated or burned, many others produce seed
profusely on mineral soil. Fire must be recycled in the environment if these
species are to exist in any numbers. One of the most spectacular sights in the
north is the reaction of the fireweed (Epilobium sp.) which, at times, covers
entire burned-over mountainsides here in the northland. A similar phenom-
enon with many other species of plants takes place in many parts of the
world and for this reason, such plants are called "fireweeds" by local people.
There are also plant relationships to the smoke from fires. One such
example is the effect of the gas, ethylene, a component of wood smoke, on
initiating flowering. A common custom in Puerto Rico in the past was to
flood the pineapple .fields with wood smoke to initiate even flowering and
thus a uniform harvest. Today, this is more easily accomplished by the use of
ethylene gas.
When a fresh bum is examined, the most obvious thing we see is the ash,
the quantity depending upon the amount and kind of fuel burned and under
what conditions of moisture, humidity, and wind the fire occurred. The ash,
however, is always high in calcium, potassium, phosphorous, and other
mineral elements. These are the chemical elements that have been released
from the organic matter in a usable soluble form and utilized by both plants
and animals. The recycling of these nutrients is of the utmost importance
here in the Alaskan environment where other processes of decay, oxidation,
and recycling of minerals is slow.
The effects of fires on plant succession are perhaps the simplest to study;
but even here, because of the variability of fire, the results can be quite
frustrating to the investigator. Perhaps one reason fire ecology has been so
late to come of age is the fact that not many studies can be conducted and
completed in 2 or 3 years, particularly in the northern environment. Plant
succession as related to certain forest tree species has been studied probably
more than any other ecological aspect. We certainly lack information on
most other vegetations as well as the relationship of animals to these succes-
sional changes, particularly in interior Alaska.
Succession of plants, however, is one of the most studied aspects of fire
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ecology, and it is not necessary to use refined and highly technical methods
to find out at least general processes. A surprising amount of information
can be obtained simply by establishing a permanent reference point such as a
concrete post and photographing the area around it before, during, and after
the fire from time to time throughout the year and from year to year. Color,
black and white, and infrared photos, if taken regularly over a period of
time, will yield much interesting information.
Fire and soil.-The effect of fire on soils has been and is quite contro-
versial for several reasons. Perhaps the foremost of these is the fact that soil
science, like forestry, developed and was nurtured in a unique
environment-the hardwood forests of Europe. It is not generally recognized
that the deciduous hardwood forests of the world are rather unique areas
when looked upon as part of the earth's biosphere. In area, they represent a
very small portion of the vegetative covering of the earth, yet the methods,
ideas, and philosophies developed there have been applied literally every-
where, exactly as was the idea that all fire was bad. It is time for ecologists,
particularly, to reexamine soil ecology in relation to the major aspects of the
globe and not some small unique area of the earth where man just happened
to develop such ideas. The most fertile, at least for man's use, are the natural
grassland soils of North America and similar regions elsewhere, not soils that
were once covered by a deciduous forest.
Because of this, I believe our present methods of study and analysis of
soils leave much to be desired. It is extremely difficult in a practical way to
depend upon soil analysis for agriculture. Soils that produce a good crop of
corn may show poor soil fertility and vice versa. In connection with studies
for heat and drought resistance in hybrid corn, I was able to conduct re-
search experiments with the Pueblo tribes of the Southwest and in particular
with the Hopi. Soil analysis by both government and private testing labora-
tories showed not enough nitrogen to produce any corn, yet consistently
these same fields were producing satisfactory yields for that particular loca-
tion. Nitrogen differences or lack of it have been part of the confusion on
burned versus unburned soils. However, it is evident to anyone who has
looked upon burned-over grassland that the resulting growth on the burn is
much darker green in color as if some quickly available form of nitrogen had
been applied. This I have found to be true, not only in many parts of North
America but in Africa and Australia as well; it is a universal principle. Lutz
(25) has also commented on this nitrogen effect with somewhat the same
results in Alaska. This effect is certainly recognized by animals universally,
because both wild and domestic animals will seek out burned areas.
Wherever this growth has been analyzed, North America, Africa, Australia,
and South America, the results have always shown the vegetation has a high
protein content as well as potassium and phosphate (14, 16, 21 ). Burton (5)
in studies of highly improved coastal bermuda (Cynodon dactylon) pastures
in the South, has reported that such pastures will produce 1 ton more of hay
per acre if burned over properly and that the effect on protein value appears
to be equivalent to a considerable application of nitrogen fertilizer. He has
suggested that the underlying reason may be the stimulation from and rapid
effect of the high calcium, potassium, phQsphate, etc.,ash on the nitrifying
bacteria in the soil. If this is so, fire may indeed have an important place in
the ecology of Alaskan soils.
The effect of the higher temperatures on the burned, blackened soil could
also have some important ecological action on the development of nitrifying
bacteria and other similar organisms, particularly with the long summer days
in the interior of Alaska. Certainly, the effect of fires on the permafrost, the
temperature of the soil, and other similar aspects would be a fruitful field of
fire ecology research. Processes taking place during 20 to 24 hours of solar
radiation might be quite different than elsewhere.
Fire and animals.-The change that fire produces in plant communities
has a long-reaching influence on the animal occupants, for plants are the
foundation of all animals and animal communities. The variability of fire,
the variability of fire impact on plants, and the variability caused by the
incomplete burning processes create an intensive and extensive diversity of
plants. These plant communities are inhabited quickly by a large variety of
animal species. Fire creates more variations in both plant and animal com-
munities than probably any other natural force.
The variations of fire, by its intensity and frequency, determine, for
example, whether the range will be occupied by moose or caribou in much
of the boreal forest regions. When the first Europeans came into the North,
caribou were found as far south as Maine and Minnesota. The fire relation-
ships of the numerous large mammal herds of east and southern Africa are
very important. Most of these animals are either grazers (grass, forbs, sedges,
etc.) or browsers (bushes). The relative proportion of these mammals com-
pared with forest animals is determined largely by the amount, intensity, and
frequency of fire (22a). Recently, I have reviewed the place of fire in the
management of wildlife habitat in the southeastern States (22). •
Speakers of many of the 149 papers presented at the first 10 Tall Timbers
Fire Ecology Conferences stressed the importance of fire in the management
of animal life in many parts of the world including the boreal north. I have
also discussed the place of fire in the lives of animals from insects to
mammals in recent years (see "Literature Cited") .
.In interior Alaska, much more intensive and long-term study of fire and its
relationships to the animal life is needed (such as Skoog's (31) dissertation
on the caribou in this region). Many of his findings are quite different from
those of others, such as Scotter (30), in the far northern tundra of Canada.
Long-term studies should be initiated at the Kenai Wildlife Refuge, particu-
larly on moose, instead of studying the effects of wildfire after long periods
of fire exclusion.
When a uniform blanket of highly flammable fuel is allowed to develop
and then catches afire, we are witnessing a phenomenon created by man, not
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a natural one. The excellent studies at Kenai (32) show a striking increase in
moose populations following severe wildfire. Must we always wait for
disastrous wildfire under unnatural conditions created by man to recycle
moose populations? The Kenai moose is a distinct form, the largest of the
species, and must have been an inhabitant of the Kenai Peninsula a long
time. Proper management needs to be practiced in place of dependence on
extensive wildfires.
Interior Alaska is a vast breeding ground for many species of waterfowl
for the North American continent. Many questions such as the following
need answers: Will fire exclusion eliminate waterfowl breeding grounds by
natural succession from open grass or sedge areas to bush, or even to
muskeg? Will fire exClusion eliminate waterfowl food plants and resting
grounds? It is my belief that lightning fires in the past have played a great
part in recycling plant succession in this region, but long-term studies are
needed before any fire exclusion policies are decided upon.
Fire in Alaska
Fire before man.-Interior Alaska, in its pristine condition before the
coming of man, was a mosaic of plant and animal communities caused by
temperature, moisture, topography, soils, and those many other climatic and
environmental aspects that can influence plants and animals. Superimposed
on this pattern was another mosaic caused or created by lightning fires. This
mixture of plants and animals varied from time to time because of changing
climatic conditions. Likewise, the numbers, intensities, etc., of lightning fires
must have varied also, and there might have been a possible periodicity of
such fires as we have now in temperature and precipitation (19, 20). Interior
Alaska is a lightning fire region today and must have been for a long time in
the past (16).
Fire and early man.-When the first men entered Alaska from Asia they
were already familiar with fire. Some of the earliest archeological evidence
on early man (Homo erectus pekiensis) and fire comes from ancient caves
with hearths near Peking, China (3). The early Alaskan people must have
used fire for such purposes as heating, attracting game, preparation of food
and easier travel. These people by such use changed this original lightning
fire mosaic to some extent. However, they were few in number and interior
Alaska is large in area so their effect was probably not too extensive.
Now I do not believe that these people or later the Eskimos and Indians
were necessarily careless with the use of fire. The forestry profession has by
repetition convinced many people, including even anthropologists and
botanists, that they were careless because early European pioneers were.
Until modern times, forests had little to offer for human sustenance. These
so-called primitive people lived in a fire environment (16, 18); and if they
had not been reasonably careful, they would have suffered-extinction by a
process of natural selection would have occurred. These people had a
knowledge of fire use and management that has been long lost to modem
man.
Native tribes in many parts of the world even today where their culture
has not been destroyed show a remarkable skill in the proper use of fire for
their particular purpose. Time will allow me to mention only two such
examples. One of the problems of poaching in some of the east African
national parks is caused by local tribesmen burning small areas in which to
set their snares when the green grass "flushes" and attracts game because of
its protein content and tenderness. I have seen such areas burned out, only 4
or 5 acres in size, in grasslands where the grass is from 6 to 8 feet tall,
without the use of any firebreaks. They can do this only because of an
innate knowledge and experience in the use and nature of grass fires. Such
"snare" areas were seen along the boundaries of Murchison Falls National
Park, and such methods are apparently common in many regions where the
local culture has not been destroyed by more modem cultures. The Masai in
east Africa show a remarkable knowledge in regard to burning fol their
cattle's needs. When they allow fires to bum into forests, it is because the
forest is of no value to them, because cows cannot eat trees.
Fire, Eskimos, and Indians.-Unfortunately, the natives' uses of fire,
except for heating and cooking purposes in Alaska, have not been recorded
to my knowledge. They knew that certain animals would be attracted by
green bums, and I believe they used fire for this purpose.
The forestry profession has made man realize the importance of wood
products in modem civilization to such an extent that man has forgotten
that he is a grassland animal, not a forest animal. For this reason, I digress to
point out that even today, in spite of our technological culture, we remain
gra.ssland animals. Our "bread" comes from cereals which are grasses, and
present studies indicate that they were developed from fire-adapted grasses
(18). The "meat" in our diet comes largely from animals that eat grass,
forbs, or shrubs and cannot in any manner be considered forest apimals.
Nearly all, if not all, of the major cereal food plants and our major domestic
livestock apparently came from fire environments. Our civilization is
founded on grains and animals that were developed from the wild by so-
called primitive people and given to us essentially as they are today; we have
simply increased yields and have yet to domesticate a major food product,
either cereal or meat. It is my belief that people who could develop such
food products also had a real fundamental knowledge of fire ecology. They
must have mastered the art of fire management to a great degree, because
their life and livelihood depended upon such skill.
However, as with the earlier peoples, the numbers of Eskimos and Indians
in interior Alaska were not great in proportion to the size of the land area, so
their fires had little permanent effect on the natural fire mosaic created by
lightning.
Fire and the European.-Probably the greatest change of all occurred with
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the beginning of the gold rush, for in their need for wood for various
purposes, miners literally stripped the mountainsides of timber. In addition,
many were careless with their fires and probably burned mountainsides on
purpose to make easier access for prospecting. Requa (28) has written:
... Old timers have told me that at the height of the Rush, there
were continuous fires burning along the entire length of the Gold
Rush route. The paddle-wheel river boats devoured firewood at a
tremendous rate and at the crest of the steamboat era, it is esti-
mated that 300,000 cords of firewood were burned each summer.
The rock-hard permafrost of the gold placer ground was thawed
with wood fires. The thawing was later carried out with wood-
fired boilers and the gold recovered with wood-fired dredges.
Consequently, nearly all available firewood within 40 miles of the
gold field was utilized.
The amount of timber that has been cut for firewood, as well as for other
purposes in more settled parts of Alaska, must be large. Zivnuska (37) has
estimated that in the conterminous 48 States the present cutting of wood-
pulp is only about equal to that cut for firewood, etc., less than 75 years
ago. Along with the cutting of timber in Alaska, man leaves more accumula-
tion of fuel such as slash and other debris on the ground than would occur
naturally. Fires, man-caused and lightning-ignited, have burned and reburned
some regions repeatedly. In some areas, man has been burning at a much
more frequent rate than would occur naturally. Hardy and Franks (11) and
Barney (1) show that the peak in numbers of the man-caused fires occur
earlier in the year than that of lightning strikes. This earlier burning may
cause different effects than later burns. They also show that man-caused fires
occur later in the year as well.
Fire Management in Alaska
Fire control versus fire management.-Fire control consists primarily of
firefighting techniques, firefighting equipment, and the necessity to get to
the fire quickly so as to suppress it. Forest fire control literature consists
largely of such data as the rate of spread and the conditions under which
fires can or cannot be extinguished. There has been an obvious lack of
interest in fire prevention by reducing hazards or flammable conditions in
Alaska. The effort in this field has been toward making people aware of fire
danger so as not to be careless with materials that will ignite fires. Fire
management is much more than fire control. It includes fire prevention-
measures to be taken to lessen fire risk-as well as an understanding of fire
ecology. City fire departments take great care that undue accumulations of
hazardous substances-do not occur, and urban areas have strict regulations in
this regard. Forest fire control agencies usually pay little attention to the
accumulation of flammable materials. This certainly cannot be construed as
frre management. In any management program, whether it be for forest,
field, or urban development, goals must be set. The goal for fire management
should be stated for various conditions, vegetations, and purposes and not
only the usual fire control goal of "allowable burn" except in instances
where fire exclusion is necessary.
Forest fire management.-Now just what do I mean by such a program.
First must come a planning stage for the interior based on the various needs
or requirements for Alaska. A growing State and economy certainly need
forest products. The most valuable forests in Alaska are the black spruce and
white spruce which are fire adapted trees, but unfortunately are adapted to
catastrophic fires primarily for regeneration purposes. The forest is vulner-
able except to the lightest of fires.
Hardy and Franks (11) reported that, of the approximately 300 million
acres of Bureau of Land Management-administered land in interior Alaska,
only 120 million acres or slightly more than a third can be considered forest
land and that, at present, only some 40 million acres can be considered of
commercial quality. That means only about 33 percent of the total forest
acreage is an economic forest and only about 1 0 percent is presently
accessible economically. Thus, the greatest priority for both fire manage-
ment as well as for forest management should be given to the 4 million acres
of accessible timber.
To utilize forests for commercial production, we must keep fire out until
after the timber operation. These forests are usually clearcut, and slash fire
or burning takes the place of the natural catastrophic fire by lightning.
However, we must also recognize that a uniform or monoculture forest over
vast areas is not a natural one. The development of continuous forests of
highly flammable material creates hazardous conditions over vast areas.
Measures should be introduced into forest management that will not allow
uniform fuel conditions to develop over large regions. This can be accom-
plished up to a certain degree by smaller and well-distributed clearcuts so as
to maintain an overall condition of different kinds of fuel. In this way, the
former natural lightning-fire mosaic can, to a certain degree, be recreated.
Urban fire management.-Probably of even greater importance to the
public are the areas around cities and towns. As the population increases,
more and more people will be living in the midst of Alaska's fire environ-
ment. In such areas, methods should be developed to lessen the risk of fire
by various methods of prevention. City fire departments have rather rigid
rules about storing or allowing flammable materials to develop around
habitations. I have noted that the Fairbanks Fire Department has used con-
trolled burning to burn down old houses that are great fire risks, and the
Fairbanks Daily Miner captions such fires as "controlled burns." In many
regions, measures are taken to reduce the flammable vegetations to the
lowest denominator or of the lowest fire risk such as grass. The Florida
Forest Service has initiated a very successful procedure in this respect. They
have organized volunteer fire departments in the various small towns and
teach them to control-burn vacant lots or areas of fire risk at a time when
17
18
the conditions are right for a cool or feeble fire. This has lowered the
incidence of wildfires around towns in north Florida considerably and in
doing so also has made many areas less dangerous and more pleasant to live
in. I cannot see why such a procedure would not work in Alaska. Training
and paying volunteers to control-burn would furnish employment and lessen
the cost of fighting large fires.
Fire management for wildlife, watershed, and recreation.-Well over 200
million acres in the interior of Alaska consist of nonforest or uneconomic
forest lands but have a great potential for wildlife and recreation. These are
also valuable because they represent a large area of watershed. I have already
discussed the reasons for considering this a natural lightning fire region, and
further investigation may prove it to be even more so. Thus, the wildlife,
including both game and fish, must be well adapted to such a fire environ-
ment. Man's efforts should be toward maintaining this habitat in as natural a
condition as is humanly possible. Much of the area represents a very unique
terrain for it is underlain with permafrost, essentially a mixture of frozen soil
and ice. It is a very special kind of environment and extremely fragile to
human interference. It is a natural lightning fire environment. Thus, any
great change or disturbance in the fire pattern may have far-reachlng
consequences. Unfortunately, the fire ecology of this region, in spite of the
fact that it is a vast breeding ground for much valuable wildlife, has been
virtually unstudied. Likewise, the effect th.ese natural fires have on the
maintenance of the fertility of the rivers and lakes has not been investigated.
The relationship of fire to the vegetation and this in turn to the protection
and maintenance of the permafrost conditions has been only cursorily
studied. No rational fire management plan can be proposed for this vast area
because of a great lack of ecological information. How much burning, over-
burning, or fire exclusion this permafrost region can tolerate without damage
remains to be learned. Investigations should be made on what wildfires are
doing, and experiments should be started to study the longtime effects of
fires of different frequencies, intensities, and kinds on the vegetations and
wildlife, and on the permafrost conditions as well. At our present state of
knowledge of this vast region, the lightning fires should be allowed to burn
unattended except in regions hazardous to human endeavors or prime forest
stands. Fortunately, both of these latter conditions are usually along the
rivers, and it might be possible in some instances to create buffer strips by
controlled burning.
Controlled or prescribed burning, although quite widely used today in
many parts of North America, Africa, and Australia, appears to be quite
unknown in Alaska. In Australia, large areas are burned annually by aerial
ignition, and these techniques have become very refined and particularly
useful in regions accessible only by aircraft. Large areas, up to 1 00 square
miles in one burn, are burned in Kruger National Park in South Africa by the
use of widely spaced firelines. Much of the permafrost region of interior
Alaska is ideally adapted to burning by aerial ignition, either by plane or by
helicopter. Such controlled burning in many sections of Alaska could lessen
the danger from large uncontrolled fires to human habitations or economic
forest lands. I would certainly suggest that attempts be made to study and
use prescribed or controlled burning in such areas in the interior where
management decisions would dictate such protection instead of relying
entirely on fire suppression.
Summary
I have discussed the basic principles of fire ecology. These are principles
b~cause the various effects are produced in like manner around the earth
where there is fuel that will burn. I have tried to point out that interior
Alaska is a lightning fire region. Fire ecology research in the Alaskan environ-
ment is virtually unknown. In those areas in the interior where lightning fires
are quite frequent and where in addition there are man-caused fires, fire
ecology research should have topmost priority. As the human population
increases, more problems will develop because interior Alaska is a fire
environment. Knowledge of the relationship of fire to forests, grasslands,
bogs, soils, lakes, and rivers in Alaska is needed if we are to manage wisely.
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Literature Cited
1. Barney, Richard J. 1969. Interior Alaska wildfires 1956-1965. Pac.
Northwest Forest & Range Exp. Sta. USDA Forest Serv. 47 p.
2. Bennett, W. D. 1960. Survey of lightning fire occurrences in Canada's
forests-1950-1959. Pulp & Pap. Res. Inst. Can. Woodlands Res. Index
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3. Black, Davidson. 1931. Evidence of the use of fire by Sinanthropus.
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27. Poulton, E. B. 1915. The habits of the Australian buprestid "fire
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34. , H. L. Beadel, and E. V. Komarek. 1961. The cooperative
quail study association. Tall Timbers Res. Sta., 500 p.
35. Wilson, A. T. 1960. Synthesis of macromolecules. Nature
188: I 007-1 009.
36. Wilson, C. T. R. 1921. Investigations on lightning discharges and on the
electric field of thunderstorms. Mon. Weather Rev. 49: 241-242.
37. Zivnuska, J. A. 1967. U.S. timber resources in a world economy. 125 p.
Baltimore: Johns Hopkins Press.
-------~-------------~~---~ -------~------------------
Fire in the Northern
Environment
23
,_
" ,_
-
24
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-'-April13-14, 1971.
Erosion, soil propert~es,
and revegetation
following a severe burn
in the Colorado Rockies
Abstract
During the summer of 1967, 20 erosion plots, 42 soil sampling points, and
50 vegetation plots were established in the Comanche Burn area, a 470-acre
burn in the Central Rocky Mountains. Observations indicate th'at erosion
during the first summer after the burn was not a serious problem but that
S011J-e erosion was occurring. The amount of rock exposed on the soil surface
is more important than slope in initiating particle movement during low
intensity storms but slope is the controlling factor during high intensity
storms. Analysis of soil physical factors show that the burn had very little
effect in spite of a complete destruction of litter and surface vegetation. This
was attributed to the coarse textured soils.
Revegetation after the burn showed a steady increase with an average of
3. 5 spruce-fir seedlings the first year and 22.4 seedlings per acre the third
year. Lodgepole pine seedlings increased from 1,185 to 1, 3 85 seedlings per
acre over the 3-year period, and aspen suckers increased from 686 to 24,000
per acre over the 3-year period. Subordinate vegetation also increased in
number and species composition.
Introduction
Wildfire on a watershed is generally a cause for alarm to the resource
manager. Of the many potential disturbances to a watershed, fire is one of
the most severe. Many studies have reported the detrimental effects of forest
denudation by fire. In addition to the economic loss of the timber, increased
flooding, increased erosion from the bare slopes, increased sediment loads in
the streams, slope failures or land slumps, and great debris flows have been
documented and studied in detail in many parts of the country.
More recently, fire has been recognized as playing an important ecological
role in maintaining the species compositions of many forest types. Aspen
and jack pine in the Lake States, longleaf pine in the South, ponderosa pine
W. D. Striffler
Department of
Watershed Sciences
Colorado State University
and
E. W. Mogren
Department of Forestry
and Wood Science
Colorado State University
Fort Collins, Colorado
25
~-
26
in the Southwest, and lodgepole pine in the Rocky Mountains are just a few
of the species whose natural regeneration and survival are related to periodic
fires.
Although naturally occurring fires apparently are advantageous to some
species, it seems likely that they are equally harmful to others, particularly
those types existing in harsh environments where the development of any
vegetative cover is a slow process. Examples of these environments would
include the northern environment, where the length of the growing season
limits growth, and arid and semiarid environments, where lack of moisture
limits growth. In these areas as well as many forested areas, damage by fire
to the watershed is generally of more concern than any ecological benefit
which may occur.
This paper examines the effects of a severe burn in the Colorado Rockies.
The effects of the fire upon soil erosion, soil properties, water quality, and
the establishment of vegetation following the burn are presented. The data
presented are based upon the work of Delp,1 Kilinc,2 Meyers,3 and Barth,4
to whom the authors express their deep appreciation.
The Comanche Burn
On August 29, 1966, at 1:30 p.m., a slash disposal fire burning in the
bottom of the empty Comanche Reservoir spread into the adjacent forest as
a result of sudden gusts of wind. By 3:00p.m., the fire crowned and spread
rapidly upslope. Two days later, on August 31, at 10:00 a.m., the fire was
under control although it was not declared out until September 29. During
the 2 days of uncontrolled burning, 4 70 acres of lodgepole pine and spruce-
fir forest, containing over 3 million board feet of timber, were destroyed.
The fire was complete, killing all the aboveground vegetation within its
boundaries. The fire was hottest in the lodgepole forest. Here, most of the
branches were burned off the trees, and the litter and duff layers were
completely consumed, leaving a deep layer of ash and bare mineral soiL The
fire was less intense in the spruce-fir forest. Although all the trees were
killed, branches remained on the trees, and in many locations, a layer of
charred duff was present on the surface. The upper margin of the fire
coincided in places with the boundary between the spruce-fir forest and
alpine tundra. Here the fire generally died out because of the lack of fuels in
the tundra.
The burn area is typical of much of the Colorado spruce-fir, lodgepole
pine country. The topography is mountainous with numerous rock outcrops
1Phil G. Delp. Soil movement following an intense burn. M.S. thesis, Colo. State Univ., 91 p.,
1968.
2 Mustafa Y. Kilinc. The effect of wildfire on soil properties. M.S. thesis, Colo. State Univ., 100 p.,
1968.
3 Alan E. Meyers. Mountain water pollution from road reconstruction and wildfire. M.S. thesis,
Colo. State Univ., 70 p., 1968.
4 Richard C. Barth. Revegetation after a subalpine wildfire. M.S. thesis, Colo. State Univ., 142 p.,
1970.
and talus slopes. Within the bum areas, steep slopes prevail with maximum
slopes up to 70 percent. However, there are several small areas of essentially
level terrain including alluvial bottoms along streams, and several upland
areas. Elevations range from about 9,300 feet at the reservoir to over 10,600
feet at the upper end with a mean of 10,000 feet.
The climate of the area is continental with cool summers and severe
winters. The mean annual temperature averages about 35° F. Precipita-
tion occurs primarily as snow between October and April. Strong downvalley
winds limit snowpack development to forested or other sheltered areas.
Soils within the bum area are primarily of the Gray Wooded and Podzol
great soil groups with small areas of alluvial sands and gravels near the stream
bottoms and colluvial deposits along the lower slopes. Surface soils over the
area are generally sandy loams with a high proportion of rock both at the
surface and within the profile.
The vegetation of the bum area was about equally divided between the
lodgepole pine type (Pinus contorta) and spruce-fir type (Picea engelmannii-
Abies lasiocarpa) with the lodgepole pine predominant on the lower eastern
side of the bum and the spruce-fir occupying the upper western side of the
bum. A clear demarcation between types did not occur but rather an inter-
grading of species of both types. Small patches of aspen (Populus
tremuloides) occurred throughout the bum. The lodgepole type averaged
about 110 square feet of basal area with 1,600 stems per acre. The spruce-fir
type had an average basal area of about 150 square feet and about 900 stems
per acre. Based on measurements in adjacent forest stands, litter and duff
accumulation ranged from 10.8 to 48.3 tons per acre with an average of 20.4
tons per acre.
Because of the fire's proximity to a water supply reservoir, there was
immediate concern that erosion might pose a problem, and revegetation
measures were undertaken. On September 3, 1,500 pounds of grass seed
were dropped by helicopter on the bum area. Because of high winds and
turbulence caused by the helicopter, the seeding was spotty with most of the
seed landing in the lower portion of the bum.
In the summer of 1967, the first growing season after the bum, a com-
prehensive study was begun to accomplish the following objectives:
1. To determine the extent of erosion and soil movement within the bum
area.
2. To determine the effect of the fire upon the hydrologic characteristics
of the soil including relative infiltration rates and some chemical and
physical soil characteristics.
3. To determine the effect on water quality of streams passing through
the bum.
4. To determine the pattern of vegetation establishment on a series of
permanent sample plots over a number of years.
27
---------~--------------------------~---
28
EROSION
Since the fire occurred at the end of the summer of 1966, only light
rainfall occurred prior to the winter snows. An inspection of the area in
December 1966 revealed no evident erosion within the bum and a layer of
ash over most of the area. By June of 1967, the ash layer had been either
compacted by the snowpack in the sheltered areas or blown off by the
winter winds in the exposed sites. At the beginning of summer, the bum area
was essentially a bare soil-bare rock surface with no sign of live vegetation.
Twenty erosion sampling plots were located on aerial photography and
then on the ground (fig. 1 ). Plots were generally located along slope transects
so as to have plots at various slope positions. Plots on slopes were located on
the upper one-third of a slope, the middle one-third, and at the base. The
percent slope and percent of surface rock were recorded at each plot. A
6-foot transect on a line perpendicular to the slope was established at each
plot to serve as a reference for soil particle displacement. Soil particles along
each transect were tagged with either an isotope (CS-134) or a fluorescent
dye. Soil particle movement downslope was measured after each storm. In
addition, changes in microrelief along the transects were measured as an
index of soil loss over the measurement period. Soil particle displacement
and soil losses were related to the amount of precipitation, .the maximum
30-minute intensity, the percent of rock cover immediately upslope from the
tagged point on the transect, the slope percent, and the area of any upslope
obstructions.
Precipitation during the summer months was very close to normal with
2.24 inches in June, 2.48 inches in July, and 2.81 inches in August. The
largest storm of the summer was on June 28 when 0.70 inch fell with a
Legend
,... --.. Fire Boundary
Erosion Plot
Figure I.-Distribution of erosion sampling plots, Comanche Bum.
--------------------------------~---------------------
maximum 30-minute intensity of 0.22 inch per hour. The second largest
storm occurred August 28 when 0.40 inch fell with a maximum 30-minute
intensity of 0.43 inch per hour. Soil particle movement on the slope was
directly related to slope percent, the percent of rock cover, and the maxi-
mum 30-minute intensity of precipitation. The maximum soil movement
measured was 25 feet on a 62-percent slope. Soil particle movement by
raindrop splash action, as measured around dye spots on level ground,
averaged about 5 feet over the summer. Total soil loss from the slopes
averaged about 0.25 inch.
In general, soil loss from the bum area was very small. Although local
erosion was frequently observed, especially where surface drainage networks
became established, most eroded particles were-redeposited downslope as the
slope gradient flattened or behind obstructions such as logs or rocks. Large
particle movement was also observed on steep slopes where rocks became
dislodged and rolled down the slope. It is evident that the lack of intense
storms and the coarse texture of the soil were the major factors restricting
erosion.
SOIL PROPERTIES
Fire is generally considered to have a deleterious effect upon forest soils.
A closer examination of the literature reveals that this is only true under
some conditions. In general, fire affects the soil if the fire is severe. Infiltra-
tion rates, organic matter contents, and porosity decrease, but bulk densities
increase. This effect is more pronounced on fine textured soils. Light bums
frequently have little or no effect on these same properties.
In the Comanche bum, 42 sampling points were established along five
transects traversing the bum (fig. 2). Of these 42 points, 26 were in the bum
Legend
,.__ Fire Boundary
"'"'----Stream
Sample transects
6 Forest Plots
o Burned Plots
D Profile Descriptions
Figure 2.-Distribution of samphng points for infiltration and soil properties.
r-
29
30
area and 16 in the adjacent unburned forest. Measurements taken at each
point include infiltration rate, bulk density, the depth of ash or litter, per-
cent of surface rock, basal area, slope, and aspect. In addition, samples were
taken for laboratory analysis of organic content and texture. In the un-
bumed forest, litter samples were taken to determine weight. Calcium, pH,
phosphorus, nitrogen, and potassium were analyzed for just a few bumed
and unbumed samples. Results of the soil tests are given in table 1.
TABLE 1.-Average burned versus unburned soil characteristics
Variable
Average 60-minute infiltration rate
(inches per hour)
Final infiltration rate (inches per hour)
Organic matter content (percent)
Bulk density (grams per cubic centimeter)
pH
Calcium (p.p.m. 1 )
Phosphorus (p.p.m.)
Nitrogen (p.p.m.)
Potassium (p.p.m.)
1 Parts per million.
Burned
12.1
9.5
1.0
1.1
5.0
525.0
13.7
1.4
123.6
Unburned
10.2
8.0
2.6
1.2
5.1
1367.3
23.0
.6
200.0
Infiltration rates were somewhat greater on the bumed plots than on the
unbumed plots. Both average rates and final infiltration rates were higher,
although differences were small and not statistically significant. The slightly
greater initial intake rates and flatter infiltration/time curve (fig. 3) are
probably due to the loose porous nature of the soil surface and ash layers in
the burn area. No evidence of nonwettability, as reported by Krammes and
DeBano 5 and others, was observed anywhere in the burn area.
Organic matter content was lower on the burned plot as would be ex-
pected following a severe fire. Bulk densities were also somewhat lower on
the burned plot, again due to the presence of ash layers on the surface.
Calcium, phosphorous, and potassium all showed a significant decrease on
the burned area, but nitrogen showed a slight increase. However, nitrogen
levels were very low on both the unburned and burned areas and the dif-
ference is probably not significant. It was assumed that the soluble nutrients
5 J. S. Krammes and L. F. DeBano. Soil wettability: a neglected factor in watershed management.
Water Resour. Res. 1: 283-286, 1965.
had been released by the fire and leached into the coarse-textured soil by
snowmelt drainage.
WATER QUALITY
Two surface streams cross the burn area. The largest, Brown's Creek,
drains a small alpine lake above the burn area. Brown's Creek has a deeply
incised channel, rocky banks, and a steep rocky bed. In some sections,
streamside vegetation was untouched by the fire. In other sections, the fire
burned close to the banks. The other stream! a small unnamed tributary
flowing directly into the reservoir, and subsequently called Charcoal Creek,
flows for about one-fourth mile through the burned lodgepole pine forest.
24
•
-+-Unburned
. 20 -•-Burned
,....
"' 6 ~ ..c: 16 .......
Ill
Ql ..c: u s::
-..1 .._,
Ql
.j.l ·~·~ . .,
12 "' d
0
-..1
.j.l + .,
"' .j.l
.-I • -..1
'1-1 + d 8
1-1
30 40 50 60
Time, minutes.
Figure 3.-Inftltration/time curves for the burned and unburned plots.
~-
l
t
r
' !
~
t :·
31
32
Stream discharge varied from 7.5 to 0.1 cubic feet per second during the
year. Although only a small proportion of the Charcoal Creek basin was
burned, it seemed likely that storm runoff and erosion from the burn could
influence the quality of water in the stream. Therefore, a small Parshall
flume was set in the stream to measure discharge, and periodic samples were
collected at the flume and at the point upstream where the stream flowed
into the burn area. Stream samples were analyzed for bacteria (coliform,
fecal coliform, fecal streptococci), dissolved solids, suspended sediment,
turbidity, pH, nitrates, sulfate, and calcium hardness. No direct influence of
the burn could be detected in any of these tests. This again may be attrib-
uted to the lack of intense storms during the sampling period and the small
size of the contributing area in the burn. Perhaps the only direct physical
effect of the fire was to expose the stream to sunlight so that, on sunny
days, a warming gradient of 2° to 3° F. per 1,000 feet of channel was
established.
REVEGETATION
At the beginning of the growing season, the burn area appeared com-
pletely devoid of vegetation. However, as the season progressed, vegetation
of various types began to appear. A study was begun to evaluate both the
initial revegetation and the factors influencing revegetation over the first
three growing seasons after the fire.
With the aid of aerial photographs and a map of the burned area, a
coordinate grid was designed and 50 random cluster points on the burn were
established (fig. 4). At each cluster point, five plots were located randomly.
These 250 plots were then located on the ground within the burned area and
permanently marked with steel stakes. Around each plot center, three con-
I''
( ' .... ' )
', o<..'\
lo ' .I ( r--""'~. < o l
..... --, ) l '......,
,/ """"~ (,... /l ' ............... ----......
,.. -..... ""\ ./ ... ' 0 0 "
.... "\ -'""'' ) 0 0 0 0 0 ......... -\
..... _ 0 "\ -0 0 '
' 0 --' 1 o o 0 o o oo ,
\ o o o o o o'-.... -./
'"....... 0 0
i. 0
'.... 0 ~"""----~
" ,,...-
' I
) I __ / 0)
'~-0--/
0 0
0
0
..--..__..,... Fire Boundary
Cluster Point
Figure 4.-Distribution of vegetation sampling plots, Comanche Bum.
centric plots were established: a 1-milacre plot on which tree reproduction
under 3 feet tall, forbs, and grasses were measured; a 5-milacre plot for
shrubs; and a 20-milacre plot for trees over 3 feet in height. Densities were
determined by using a modification of the Braun-Blanquet density cate-
gories. Each species of shrub, forb, and grass was assigned one of four cate-
gories: abundant, common, occasional, or rare. Density of tree reproduction
was determined quantitatively by counting the number of individual stems
for each species on each plot.
At each cluster point, site and prefire stand conditions were measured.
Aspect, slope percent, position on slope, and presence of surface rock were
recorded. For the prefire stand, basal area, average tree diameter, and
number of steins per acre were determined. Soil samples were taken, and pH
and soluble salts were measured. To establish a base for comparison, similar
sites adjacent to the bum were established and measured in the same fashion
as were the plots on the bum.
The bum was divided into two areas on the basis of the prefire forest
types, spruce-fir and lodgepqle pine, and data were analyzed separately for
the first and third year following the bum. Eighty-five plots were in the
spruce area, and the remaining 165 plots were in the lodgepole area. Fre-
quencies of occurrence on the plots are shown in figures 5 and 6.
Tree Reproduction
On the spruce-fir area, tree reproduction occurred on only 4 percent of
the plots 1 year after the bum. This had increased to 13 percent at the end
of the third year. Lodgepole pine and subalpine fir were the species present
and in about equal numbers. Engelmann spruce, the dominant tree in the
prefire stand, had not reproduced on the burn at the end of the third year.
On the lodgepole pine area, tree reproduction included two species, lodge-
pole pine and aspen. One year after the bum, lodgepole pine was found on
39 percent of the plots and aspen on 27 percent, giving tree reproduction on
55 percent of all burned plots. Two years later, lodgepole pine had increased
to 46 percent and aspen to 48 percent, giving tree reproduction on 63
percent of all plots.
An analysis using Fumival's binary screen was made to determine which if
any of the measured variables were related to the density of lodgepole pine
seedlings. Four variables were found to be related significantly to seedling
density 1 year after fire: position on slope, density of shrub vegetation,
prefire tree basal area, and percent slope. When the data were analyzed 2
years later, only three variables proved significant: aspect, position on slope,
and density of herbaceous vegetation.
Aspect, position on slope, and percent slope undoubtedly are related to
the tree-water relationship. Because these variables influence available water
in a negative fashion, tree density decreased. Tree basal area of prefire stands
was related to seed supply. As basal area increased, available seed increased
r
F
[_
33
34
as did subsequent seedling density. Density of shrubs and density of
herbaceous vegetation influenced the occurrence of seedlings through
competition. As the density of shrubs and forbs increased, tree seedling
density decreased.
Unburned 1967 1969
Figure 5.-Frequency of occurrence of vegetation types in the spruce-fir plots,
Comanche Bum and adjacent unburned area.
Unburned
Ul
QJ
Ul
Ul
Ill
'"' C!l
1967, 1969
Figure 6.-Frequency of occurrence of vegetation types in the lodgepole pine plots,
Comanche Bum a:nd adjacent unburned area.
Subordinate Vegetation
In order to compare the vegetative response following the fire with what
was present on the area prior to the burn, a series of similar site plots were
established adjacent to the burned area in unburned forest which were
considered representative of the prefire conditions on the burn. Comparisons
in both areas were made and are shown in figures 5 and 6.
On the lodgepole area, the numbers of species present on the burn in
relation to the number found on the similar site were somewhat different.
On the similar site plots, 11 species of shrubs were found; whereas on the
burn, seven species were present after 1 year and 10 species after 3 years. On
the similar site, 11 species of forbs were found; on the burn, 13 species after
1 year and 19 after 3 years. Three species of grasses were present on the
similar sites; on the burn, seven species after 1 year and nine after 3 years.
The presence of four of the species of grasses on the burn resulted from
artificial seeding just after the burn.
Summary
Spruce-Fir Area
Tree reproduction in this area was sparse. Density after 1 year was 3.5
seedlings per acre and increased to only 22.4 seedlings per acre after 3 years.
The failure of this area to restock was attributed to lack of adequate seed
source.
A total of 20 subordinate species were found 1 year after the burn com-
pared with 29 found 2 years later. Species that sprouted from surviving
rootstock were shade tolerant and perennial. Invading species, 87 percent of
the species recorded, were generally intolerant of shade, and many were
annuals. Density of subordinate vegetation was highest in moist locations.
The density index increased during the study period, but at the end of the
third year, it was only a fraction of the density index calculated for the
unburned stand.
Lodgepole Area
Tree reproduction in the portion of this area that was primarily aspen in
the prefire forest consisted of numerous aspen suckers and a few widely
scattered lodgepole pine seedlings. Suckers increased from 686 per acre 1
year after fire to 23,909 per acre 2 years later. Occurrence of aspen suckers
was due to the abundance of this species in the prefire stand.
In the typically lodgepole pine stands, most pine seedlings were estab-
lished the first year after the fire. Density was 1,385 seedlings per acre 3
years following the fire which was only a slight increase over the 1,185 per
acre noted after 1 year. Seedling density increased as position on slope
decreased and as herbaceous and shrub densities decreased. Moisture was
considered to be the key factor in reproduction density.
~---------~
L E
35
36
~~-----~-----------
Subordinate vegetation was present on 97 percent of plots 1 year follow-
ing the fire. Of the 46 different species recorded, 17 were recorded 1 year
after fire and 43 were recorded 2 years later. The grass layer had the highest
density index and the forb layer th.e lowest even though 48 percent of the
plant species on the burn were forbs. In general terms, the subordinate
vegetation was favored by areas with low position on slope, a high prefire
tree basal area, and a greater number of prefire tree stems per acre. Such sites
had the deeper soils, were shaded by residual snags, and were generally
moist. Although fewer species were found on the unburned stands, the
density index was about the same as for the burned stands.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Apri113-14, 1971.
Effects of fire and fire control
on soil and water relations
in northern forests-
a preliminary review 1
Abstract
Research data and literature are sparse on fire in the taiga and subarctic
zones, especially regarding effects of fire on soil and water relations and on
associated resource management considerations. In the scattered existing
work, there is disagreement regarding effects of fire on soil temperatures,
permafrost degradation, destruction of the organic mat, soil erosion, and
other factors; but this is partially expected considering the wide variation in
soils, geology, climate, and vegetation of subarctic data sources. Some
observers indicate more serious damage from past fire suppression methods
than from the fires themselves. A brief, preliminary review of work pertain-
ing to effects of fire in northern forests is presented. Much additional work is
needed to delineate the problems and relationships.
Alaska, one-fifth the size of the contiguous 48 States, has been greatly
affected by fires, and over 80 percent of the interior has been burned or
reburned in recent history. Alaskan fires burn an average of 1.1 million acres
annually; in severe years, they burn several million acres (11). Suppression
costs for 1969 were an estimated $24 million for 512 fires which burned
4,231, 711 acres and involved construction of several hundred miles of fire-
lines. Some $1 7 million damage resulted even so. 2
Recovery in the boreal forest zones is much slower than in other climes
and may require 150 years for a spruce stand or a caribou lichen range.
Actual erosion and siltation of streams are only suspected. Effects of fire and
of control on permafrost areas is a critical but relatively unknown factor. In
many situations, a thick vegetative mat exerts principal control on the soil
thermal regime. When this mat is modified or removed, the frozen-in-place
silt can display marked mobility upon melting. Slippage of soil and siltation
of streams can be severe even on seemingly slopeless terrain.
1 This work was supported in part by the Pacific Northwest Forest and Range Experiment Station,
Forest Service, U.S. Department of Agriculture (grant FS-PNW-Gr 1-71).
2 Preliminary statistics, Alaska Forest Fire Council, 1970.
Owane J. Sykes
Department of Land
Resources and
Agricultural Sciences,
University of Alaska,
College, Alaska
37
' -
' ~-
38
. ····---···----------------
Hutchison (13), Lutz (28, 30), and Zasada and Gregory (41) provide
recent analyses of the present and historical status of forest resources of
interior Alaska.
Literature on fire was summarized by Cushwa (8), primarily with refer-
ence to the lower 48 States. Korchagin (16) and Beliakov (5) describe work
on fire in Russia; Kujala (18), for northern Finland; and Uggla (40), for
northern Sweden, with some reference to effects of fire. A compilation of
Canadian fire research literature was prepared by Ramsey (35) and a bibliog-
raphy on fire in far northern regions was presented by Larson (20). Those
works present a compilation of work on fire in the northern climes in gen-
eral. However, as Hardy and Franks (11) state, "Literature pertinent to fire
and control in interior Alaska is scarce." Much of this limited research work
in Alaska to date has necessarily been on the more immediate demands of
fire prediction, fire danger indices, and fire control, rather than on long-
range effects of fire relative to the environment and to resource management
objectives. Lutz's work (22, 23, 24, 25, 26, 27, 28, 29, 30, 31) on fire
ecology is the primary base of such information in Alaska.
A comprehensive analysis of Alaskan fire activity and statistics to 1958
was prepared by Hardy and Franks (11) and was updated to 1965 by Barney
(3). Frail's report3 provides experience from a prescribed burn in south-
eastern Alaska, though such information probably does not apply to the
subarctic interior.
Organic Matter
Work on soil-plant-moisture effects from fire appears to be relatively non-
existent for Alaska and what little information is available is highly contra-
dictory. Organic material is integrally related to soil condition and especially
to the water relations. Austin and Baisinger (2), working in the Pacific
Northwest, considered the removal of organic matter by fire as having more
significance than all other effects combined. They noted the beneficial
importance of unincorporated organic matter as an agent in: (1) improving
soil aeration, (2) storing plant nutrients, (3) reducing moisture losses through
evaporation, (4) improving soil structure, (5) inhibiting compaction and
crusting, (6) checking erosion, and (7) increasing water-holding capacities.
Scotter (36) indicates serious destruction of the organic layer by fires in
northern Canada resulting in exposure of as much as 35 to 40 percent of the
mineral-soil surface area. Similarly, in Alaska, Lutz (25) observed burning to
mineral soil involving 30 to 40 percent of the surface area even in fires so
severe as to kill all trees. Other observers have indicated lower exposures.
Lotspeich et al. (21) in their study of the 1967 Chicken Fire in eastern
interior Alaska found that the organic layer was not burned down to mineral
soil. Henderson and Muraro (12) discuss effects of moisture content of the
organic layer on forest fires. Of course, fuel and burning conditions cause
3 Lynn D. Frail. Report of prescribed burn, Strapass #2, Kosciusko Island. 1962. Unpublished
report on file at South Tongass National Forest, Juneau, Alaska.
variations in response, but there seems to be little quantitative information
to indicate relative importance of the various factors or to quantitatively
describe which situations are most common throughout the northern vegeta-
tion types.
Water Relations
Lutz (25) postulates that the overall moisture relation effects from fire are
more pronounced on the southern slopes where the moisture balanceis more
critical. Quirk and Sykes (34) found soil moisture contents 10-15 percent
higher in unburned spruce than on a previously burned south slope, but they
implied this factor to be causal in preventing fire rather than an effect from
fire. Patrie and Black (33) provide evapotranspiration criteria adapted to
Alaska, but the sparsity of long-term climatic data made computations diffi-
cult and highly variable. They indicate that the University Experiment Sta-
tion at Fairbanks is the only station in the State with sufficient published
data to allow comparison by all of the three most common methods:
Penman, Thomthwaite, and evaporation pan.
Hydrology and Erosion
There is little information or agreement on the hydrological effects of fire
in Alaskan taiga zones. Shimkin (38) indicates that, due to permanently
frozen ground in the Arctic areas, the flooding, eroding, and silt-carrying
capacities of Arctic rivers are nearly four times as great as experienced in
temperate areas. Many knowledgeable local residents and resource observers
indicate serious erosion from burned areas. Ellsworth and Davenport (1 0) in
their 1915 work in the Yukon-Tanana region suggest that the heavy moss
layer is the principal regulator in the distribution of the summer runoff, and
they cite examples and local opinions wherein burned-over areas yield more
rapid "flashy" runoff. Bob Marshall (32) and Auer (1) express similar senti-
ment. After a recent fire in the Salcha River headwaters, the Big Delta Soil
Conservation Sub-District expressed concern over the serious erosion and
siltation of the river.
However, Lutz (25) indicates erosion on burned-over areas is surprisingly
small in spite of the fact that the soil properties would lead one to conclude
that they were easily eroded. Scotter (36) feels erosionfollowing forest fires
in northern Saskatchewan is not serious. In fact, several years after a bum,
he found increased infiltration rates on the burned-over soils compared with
unburned soil and felt this would reduce the threat of erosion. This infiltra-
tion data is in contrast to that of other workers in temperate zones where
infiltration rates on burned-over areas have been slower than on unburned
areas ( 4, 7, 15), some as much as 40 perce:nt slower (14). In California,
uneven penetration of soil moisture after fires has been attributed to a
hydrophobic organic coating of soil particles, sometimes even preventing
water penetration beyond 1 or 2 inches into dry soil (17).
r
39
40
Fire Control Lines
Many observers indicate more serious damage from present fire suppres-
sion methods than from the fire itself. For example, Lotspeich et al. (21) in
their study of the 1967 Chicken Fire found negligible indication of erosion
in actual burned areas but drastic erosion and degradation along fire control
lines and "cat trails." On some permafrost terrain, even in seemingly flat
basins of imperceptible slope, the severity of such catline erosion and the soil
volume displacement can be astonishing at times. The insulative mat of
mosses and lichens is usually 4 to 12 inches thick and, even in late summer,
the underlying active (seasonal thaw) layer of soil frequently has a maximum
depth of only 5-l 0 inches. The permanently frozen soil below may range
from low to higl1 in ice (water) content. Of course, for an effective fireline,
the mat must be completely removed, leaving mineral soil. Open, thus, to
long-day radiation without an insulative cover the thermal degradation and
erosion can take place readily.
Lachenbruch (19) made theoretical estimates of effects of a heated pipe-
line in permafrost, causing thermal degradation of high ice-content soil into a
slurry condition. Adapting Lachenbruch's figures for laminar flow of visco-
plastic fluids to a soil slurry (of 1 0 3 poise viscosity) 6 inches deep in the
trench of an eroding catline, an astonishing flow rate is projected of 0.05
mile per day on a "flat" slope of only 1 foot per mile. Theoretical velocity
of flow on only a 25-foot-per-mile slope is 1 mile per day. Increasing the
depth of the slurry layer fivefold ' increases the theoretical velocity by 20
times. Though this comparison is admittedly a tenuous adaptation, it does
point out the great potential instability of permafrost soil exposed by fire-
line construction.
The residual effects from fire control techniques have caused considerable
concern among resource managers (9), and various in-service reports and
rehabilitation endeavors have been undertaken during recent years. The
Bureau of Land Management initiated one· such administrative revegetation
study in 1969 near the Taylor Highway in eastern Alaska (6).
Soil Temperature
Soil temperature regimes are significantly altered by fire. Most workers in
temperate zones, except Shirley (39), have found increased temperatures on
burned-over areas as a result of removal of insulative material and greater
absorbance of radiant energy by the darker, charred surface. Kittredge (15)
found a 20° F. difference at the l-inch depth. In interior Alaska, Quirk and
Sykes (34) observed a 5° F. higher soil temperature at 1 inch in a previously
burned 40-year-old birch stand compared with a 200-year-old white spruce
stand; such differences penetrated the profile. to over 16 inches. Scotter (36)
found burned-over areas in northern Saskatchewan to average 10.5° F. high-
er at the l-inch depth and 9. 7° F. at the 3-inch depth. Such relationships are
confirmed by Lutz (25) and numerous observations have been made on the
resulting recession of the permafrost zone after fire. Lotspeich et al. (21),
however, found no change in depth of permafrost in their study 1 year after
the -burn.
Summary
Though many discrepancies are evident in the existing literature, this is to
be expected considering the vast, widely separated regions from which the
meager data are derived and the differences in soil, geology, climate, vegeta-
tion, and fire control activities. Several study projects are underway, how-
ever. It is clear that much work is critically needed to delineate the problems
and the relationships involved.
Literature Cited
1. Auer, Vaino. 1928. Present peat bogs in southeastern Canada. Nyky-
isista Kaakkois-Kanadan Soista. Inst. Quaestionum Forest. Finland,
Commun. 13: 1-55. [In Finnish.]
2. Austin, R. C., and D. H. Baisinger. 1955. Some effects of burning on
forest soils of western Oregon and Washington. J. Forest. 53: 275-280.
3. Barney, Richard J. 1969. Interior Alaska wildfires 1956-1965. USDA
Forest Serv. Pac. Northwest Forest & Range Exp. Sta., 47 p., illus.
4. Beaton, J. D. 1959. The influence of burning on the soil in the timber
range of Lac de Jeune, British Columbia. I. Physical properties.
II. Chemical properties. Can. J. Soil. Sci. 39: 1-11.
5. Beliakov, Mikhail F edorovich. 1946. Some data on for est fires in the
near (western) Polar Ural. Prir., Leningrad. 11: 88-90. [In Russian.]
6. Bolstad, Roger. 1971. Catline rehabilitation and restoration. In Fire in
the northern environment, a symposium, p. 107-116, illus. Pac. North-
west Forest & Range Exp. Sta., Portland, Oreg.
41
42
7. Burns, P. Y. 1952. Effect of fire on forest soils in the pine barren region
of New Jersey. Yale Univ. Sch. Forest. Bull. 57,50 p.
8. Cushwa, Charles T. 1968. Fire: a summary of literature in the United
States from the mid-1920's to 1966. USDA Forest Serv. Southeast.
Forest Exp. Sta., 117 p.
9. DeLeonardis, Salvatore. 1971. Effects of fire and fire control methods
in interior Alaska. In Fire in the northern environment, a symposium,
p. 101-105, illus. Pac. Northwest Forest & Range Exp. Sta., Portland,
Oreg.
10. Ellsworth, C. E., and R. W. Davenport. 1915. Surface water supply of
the Yukon-Tanana region, Alaska. U.S. Geol. Surv. Water Supply Pap.
342,343 p.
11. Hardy, Charles E., and James W. Franks. 1963. Forest fires in Alaska.
USDA Forest Serv. Res. Pap. INT-5, 163 p. Intermountain Forest &
Range Exp. Sta.
12. Henderson, R. C., and S. J. Muraro. 1968. Effect of organic layer
moisture on prescribed burning. Can. Dep. Forest. Rural Develop.,
Forest. Br. Inform. Rep. BC-X-14.
13. Hutchison, 0. Keith. 1967. Alaska's forest resource. USDA Forest Serv.
Resour. Bull. PNW-19, 74 p., illus. Pac. Northwest Forest & Range Exp.
Sta.
14. Johnson, W. M. 1940. Infiltration capacity of a forest soil as influenced
by litter. J. Forest. 38: 520.
15. Kittredge, J. 1938. Comparative infiltration in the forest and open. J.
Forest. 36: 1156-1157.
16. Korchagin, Aleksandr Aleksandrovich. 1954. The effect of fires on the
forest vegetation and its re-establishment after the fire in the European
north. Akad. nauk. SSSR. Bot. Inst. Tr. Ser. 3, Geobot., vyp. 9,
p. 75-149. [In Russian.]
17. Krammes, J. S., and L. F. DeBano. 1965. Soil wettability: a neglected
factor in watershed management. Water Resour. Res. 1 ( 12): 283-286.
18. Kujala, Viljo Vilho. 1926. Investigations on the influence of forest fires
on the forest flora in northern Finland. Helsinfors. Metsatietellinen
tutkimuslaitos. Julkaisuja 10(5): 41. [In Finnish.]
19. Lachenbruch, A. H. 1970. Some estimates of the thermal effects of a
heated pipeline in permafrost. U.S. Geol. Surv. Circ. 632, 23 p.
20. Larson, Signe M. 1969. Fire in far northern regions-a bibliography. U.S.
Dep. Interior, Dep. Libr., Bibliogr. Ser. 14, 36 p.
21. Lotspeich, Fred B., E. W. Mueller, and P. T. Frey. 1970. Effects oflarge
scale forest fires on water quality in interior Alaska. Fed. Water Pollut.
Contr. Admin., Alaska Water Lab., 115 p.
22. Lutz, Harold John. 1950. Forest fires in Alaska damage more than
timber. USDA Forest Serv. Alaska Forest Res. Center Tech. Note 5, 1 p.
23. . 1951. Ecological effects of forest fires in the interior of
Alaska. 1st Alaskan Sci. Conf. Proc. Nat. Res. Counc. Bull. 122,
1950: 120.
24. . 1952. Effects of fire on soils in northern forests. 3rd
Alaskan Sci. Con f. Proc. 1952: 54-55.
25. . 1956. Ecological effects of forest fires in the interior of
Alaska. U.S. Dep. Agr. Tech. Bull. 1133, 121 p.
26. . 1957. Forest-site relations in the Alaskan interior. 8th
Alaskan Sci. Con[ Proc. 1957: 120-122.
27. . 1959. Aboriginal man and white man as historical causes
of fires in the boreal forest, with particular reference to Alaska. Yale
Univ. Sch. Forest. Bull. 65, 49 p.
28. • 1960. Fire as an ecological factor in the boreal forest of
Alaska. J. Forest. 58: 454-460.
29. . 1960. History of the early occurrence of moose on the
Kenai Peninsula and in other sections of Alaska. Alaska Forest Res.
Center USDA Forest Serv. Misc. Publ. 1.
30. . 1963. Early forest conditions in the Alaska interior; a
historical account with original sources. USDA Forest Serv. Northern
Forest Exp. Sta., 74 p.
31. and A. P. Caporaso. 1958. Vegetation and topographic
situation as indicators of forest land classes in air-photo interpretation
of the Alaska interior. USDA Forest Serv. Alaska Forest Res. Center
Sta. Pap. 1 0, 31 p.
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It
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44
32. Marshall, Robert. 1933. Arctic village. 399 p. New York: Smith & Haas.
33. Patrie, James H., and Peter E. Black. 1968. Potential evapotranspiration
and climate in Alaska by Thornthwaite's classification. USDA Forest
Serv. Res. Pap. PNW-71, 28 p., illus. Pac. Northwest Forest & Range
Exp. Sta.
34. Quirk, William A., and Dwane J. Sykes. 1971. White spr~ce stringers in a
fire-patterned landscape in interior Alaska. In Fire in the northern
environment, a symposium, p. 179-197, ill us. Pac. Northwest Forest &
Range Exp. Sta., Portland, Oreg.
35. Ramsey, G. S. 1966. Bibliography of departmental forest fire research
literature. Can. Forest Fire Res. Inst. Rep. FF-X-2.
36. Scotter, George W. 1964. Effects of forest fires on the winter range of
barren-ground caribou in northern Saskatchewan. Can. Wildlife Serv.,
Wildlife Manage. Bull., Ser. 1, No. 18, 111 p.
37. . 1967. Effects of fire on barren-ground caribou and their
forest habitat in northern Canada. 32d N. Amer. Wildlife Conf. Trans.,
p. 246-259.
38. Shimkin, Demitri B. 1951. Fort Yukon, Alaska-an essay in human
ecology. Alaska Develop. Board, Juneau, 50 p.
39. Shirley, H. L. 1932. Does light burning stimulate aspen suckers? J.
Forest. 30: 419-420.
40. Uggla, Evald. 1958. Ecological effects of fire on north Swedish forests.
18 p. Uppsala, Sweden: Almqvist and Wiksell.
41. Zasada, John C., and Robert A. Gregory. 1969. Regeneration of white
spruce with reference to interior Alaska: a literature review. USDA
Forest Serv. Res. Pap. PNW-79, 37 p. Pac. Northwest Forest & Range
Exp. Sta.
~~--------~---
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Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Effects of fire
in the taiga
on the environment
Abstract
Findings from a study of fire effects on the aquatic environment lead to
the conclusion that the fire had fewer deleterious effects than did activities
from fighting the fire-improper siting of "cat" lines as an example. These
findings were important in decisions by land management agencies to revise
recommended fire fighting methods.
In Alaska, and in other areas with similar climates, the presence of perma-
frost is a complicating factor that requires careful consideration when
making decisions on where and how to contain a fire. A selected control
strategy may result in more damage than letting a given fire spread and burn
itself out. Heavy applications of phosphate-base retardants may cause early
eutrophication of lakes. A decision must be made on intensive versus nomi-
nal efforts to control a given fire; each is unique and the total ecosystem,
with variations, must be considered in addition to the economic value of the
forest resource-all these lead to the conclusion that decisions on how to
fight extensive wildfires in the taiga require knowledge that frequently is not
available. Lack of such information may result in some unexpected side
effects. All land managers must constantly seek to improve their under-
standing of the taiga ecosystem to better prepare them to make decisions
regarding where the effer:ts of a chosen plan of action will lead.
Introduction
A study investigating the effects of forest fires on water quality was
reported by the Alaska Water Laboratory, Federal Water Quality Adminis-
tration, in February 1970. The fire area studied is located east of the Taylor
Highway near Chicken, Alaska. The fire was started by lightning on July 23,
1966; and by September 13, when it was brought under control, more than
250,000 acres had burned.
Frederick B. Lotspeich
Ernst W. Mueller
Environmental
Protection Agency
Alaska Water
Laboratory
College, Alaska
45
46
----------~~--~~ -~~----~~-
The watersheds of a number of small streams were completely burned. In
addition, large areas of the drainage basin of larger streams such as the West
Fork, Dennison River, and Big Timber Creek were also burned. Sampling
stations were established above, within, and below the burned areas. Sites
were sampled for soil and water chemistry and aquatic bottom fauna for 2
years following the fire.
This study concluded that fire fighting activities may contribute as much
to water pollution as do the residual effects of the fire. Specifically, pollu-
tiOJ1 of water, as defined in this study, \Vasc;aused by three CQnstituents---:silt,
organic material, and soluble salts. Stream turbidity, originating from silt
released by erosion from bulldozed fireline construction, was significant for
several summer seasons following the fire. This persistent source of pollutant
arose because fireline planning did not consider the long-term effects of
erosion as influenced by permafrost that continued melting after the fire was
out. Organics released by the burning and washed into the streams were
considered as less significant pollutants, although they did contribute to
additional turbidity for from 1 to 2 years after burning. These effects gradu-
ally decreased as vegetation became established, and permafrost had less
influence on organic material than on erosion. The third pollutant, soluble
salts, was added in small quantity and is not believed to be significant
although increases of greater magnitude may be significant immediately after
a fire.
As a direct result of these conclusions, Bureau of Land Management re-
vised their firefighting procedures to avoid extensive erosion of fire trails and
the resulting sedimentation. Fire suppression supervisors have been issued
revised instructions to carefully consider potential erosion problems when
establishing fire trails. Let us now turn to other aspects of fire-both wild
and controlled.
Effects of Fire Other than Those
Resulting from Suppression
When deciding whether to attempt fire control in wild lands, several
factors must be considered. Not only the economic value of the resource
comes under scrutiny but also the probable effects and costs of suppression.
It must be recognized that the Alaska vegetational mosaic resulted from fire
and that wildlife migrations evolved under these shifting fire patterns. Only
periodic burning can preserve a vegetational complex that constitutes range
for much wildlife. Normal plant succession after severe burning results in
slowly changing habitats that certain native game species require. The deci-
sion to alter this pattern by controlling fire or permitting burning should
result from a consideration of factors in addition to the threat to human
habitation and economic values.
---~~-~~~·
~-
If burning is not severe enough to destroy the usual deep moss cover of
most of the taiga, erosion does not present a problem. Permafrost may melt
to greater depths for a few years after a fire, but this selclgm introduces a
problem of erosion unless the overlying vegetation mat is removed, either by
severe burning or heavy equipment. Once melting starts on exposed soil, it
releases silt that may cause sedimentation of stream waters-even where
gradients are so gentle they would not erode normally. The release of silt
through melting, rather than true erosion, is the factor that may cause sedi-
mentation of streams draining a burned area.
- ------
Soluble organics may be released by the burning process and give brown
colors to streams. However, many streams of the taiga are naturally brown
from organics leached from muskeg areas within the drainage basin. Whether
an increase in color as a result of fire interferes with the normal function.ing
of the aquatic ecosystem is a matter of conjecture at this time. These aquatic
communities evolved and are living in highly colored waters; however, their
tolerance of higher concentrations of these colored organic substances is
unknown.
Soluble salts released by burning may be lost to the soil and enter the
surface waters under certain runoff conditions. However, resultant concen-
trations are relatively low and may never reach levels that could be t~rnied
serious pollution problems.
l:n,troduction of Chemicals from Retardants
Used in Fire Control
Since many fires occur in areas inaccessible to ground crews, heavy use is
made of chemical retardants dropped from planes. One of the main materials
now being used is a compound containing ammonium phosphate with trace
quantities of ferric oxide and an organic binder. When used in heavy conc~n
trations, it can cause an unacceptably high concentration of nitrogen and
phosphorous nutrients in streams and lakes. Eutrophication is a much more
serious phenomenon in lakes than in streams, because lakes act as a sipk
collecting phosphates and high levels of this nutrient might seriously change
the lake ecosystem.
Sometimes the decisionmaker must use retardants intensively regardless of
effects on other resources-an example might be when a community or
village is threatened by fire and intensive use of retardant may prevent heavy
damage. At any rate, the decision on whether, where, when, and how to use
chemical reta,rdants depends on factors that must be known in advance of an
action; therefore, some estimate of results must be predicted. Knowledge of
ecosystem dynamics and how they react to fire and efforts to control it, is a
worthy requirement of fire control supervisors. With such information, fire
control supervisors can make rational decisions on whether an intense or
minimal effort with chemicals can be made with minimum damage to other
affected resources.
47
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48
Economics and Ecology
Before an intense fire-fighting effort is mobilized, the economic worth of
the total burned area must be considered. Control efforts might cost more
than the economic value of the resource that is presumed to be destroyed by
fire. This is especially relevant when burning might even enhance the value of
wildlife range and no other more valuable resource is threatened. Recent
studies in Minnesota and Georgia indicate that fire may be used as an ecological
tool to increase the value of given areas. Scenic values may far outweigh any
economic consideration and require an intense effort of control even though
the area has a low overall value as timber or wildlife range. However, before a
decision is made to control or not control a fire, fire control supervisors
must be in a position of strength, through ecological knowledge, and be able
to predict what will be the result of a given course of action.
Smoke from extensive fires is certainly an economic factor through its
effect on visibility and as an irritant. Aircraft may be unable to make sched-
uled landings when smoke is thick. As an irritant to all life, smoke has
received little attention but probably has some disagreeable effects even if
only temporary. The effects of many days of thick smoke on the taiga forest
is unknown, but intuitively we can reason that restriction of light and irrita-
tion have deleterious effects. Thus, the effects of smoke must be considered
as a factor when deciding on the course of action to be taken to control
wildfire.
Physical Factors to Consider
Several physical factors of the taiga ecosystem influence the ultimate
outcome of a previously planned system of fire control and the resultant
effect on the aquatic environment. One such factor, permafrost, was dis-
cussed earlier and can be suspected to be discontinuous throughout interior
Alaska. The planning of firelines and clearing operations must always
consider effects from permafrost disturbance. Failure to adequately appraise
permafrost can result in long-lasting erosion that may be more serious than
the total effect of burning. Through proper site planning for equipment-
constructed fire trails, obvious areas of ice can be avoided and trails restrict-
ed to well-drained rocky areas as much as possible.
Geomorphology influences the course of a fire-shape and slope of hills
help determine rate and extent of burning; aspect or direction of exposure
may limit one slope to a particular environmental climax community in
contrast to one entirely different on the opposite slope. These contrasting
climaxes (or successional units) may have different rates of burning: the
climax forest may be stunted black spruce on northern slopes and birch and
white spruce on the south slope. Valley-ridge systems and prevailing winds
also influence fire planning. Contrasting slope directions may also have dif-
fering depths of moss cover. If a fire is not severe enough to destroy this
protective cover, erosion may not be serious unless fire trails have removed
this cover.
Precipitation and relative humidity are important factors governing the
planned suppression of fires. If heavier than usual rainfall precedes a fire, the
moss layer will contain more moisture and resist burning, whereas drier than
usual conditions may result in complete destruction of the protective moss
layer. Under these latter conditions, erosion may become serious with
resultant extensive stream sedimentation. The quantity of fuel available also
strongly influences the severity of burning. If a burn passes through a
healthy forest, less flammable fuel is available than on an area burned a few
years before where the trees have been killed and allowed to dry while
standing.
Need for More Ecological Knowledge
Throughout this discussion, we have stressed that decisions being made on
how to control wildfires in the taiga should and must depend on environ-
mental knowledge. A wrong decision may have unexpected results, usually
to the environment's detriment. The work referred to earlier is an example
of an area where fire fighting methods may have resulted in more damage to
water quality than did the fire itself. Persons responsible for making these
far-reaching judgments need information that many times is not available,
and they reach a decision based on experience or conjecture. Badly needed is
a research program to study the ecological, social, and economic effects of
fires in the taiga.
Only by having information derived from previous research can evalua-
tions be made of the consequences of a decided course of action. The
research referred to in the introduction was a small step toward under-
standing how wildfire affects our aquatic environment. A long-range program
of field investigation to study all aspects of fire ecology in the taiga is
needed. Such research should include the study of direct, immediate effects
of fire on soils, vegetation, and wildlife and how these in turn affect the
aquatic ecosystems. Long-range objectives should be the study of plant and
animal succession to establish criteria for predicting results of a given fire
under controlled and uncontrolled circumstances.
Even with present incomplete information, much can be accomplished in
predicting the results of a particular course of action if all persons making
such decisions are aware of environmental factors and how they may be
used. Supervisors at all levels and other professional persons likely to become
involved in fire control should constantly strive to improve their knowledge
of ecology and environmental requirements of the taiga. By applying
management practices that have a predictable effect, we can avoid some
consequences of poor judgments based on "hunches" or otherwise question-
able reasons for decisionmaking.
49
"-. • ~·
' • t
'
50
-----~---·-----
--~---~-
All managers of renewable resources should be thoroughly trained in the
theory and practice of ecological management of natural resources. Emphasis
in the past has been on the economic aspect of management; hence, the
ecosystems have not received the attention they deserve. As we gain more
and niore understanding of ecosystem dynamics, ecomanagers can apply
their knowledge to the management of a given natural unit and gain the
optimum benefit from it without damaging other associated resources. Most
laws and regulations have been written for the benefit of man and seldom do
managers consider the requirements of the ecosystems involved. Ultimately
all of man's existence depends on maintaining an environment suitable to
sustain all life, however fragile, not man's exclusively. Unless we take imme-
diate action to gain and apply ecological knowledge to forestall predictable
deleterious consequences of our activities, we will be faced with the alter-
native of a deteriorating worldwide environment.
In the taiga, fire is only one of these environmental factors; but because of
its overriding control over the life pattern in this area, we must learn to use it
to gain the optimum benefits for this biome. When this management concept
is attained, man will also benefit, because as we learn to live ecologically as
part of any biome, we stand to gain in the long run by less destruction of the
base upon which we depend for survival.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Wildfires in Alaska-
some historical and
projected effects
and aspects
Abstract
This paper discusses some of the historical aspects of wildfires in interior
Alaska with particular reference to the period from 1940 to the present.
Several speculations are made on the basis of recent records relative to fire
impact or effects. The need to obtainquantitative impact information is also
discussed. • ·-
Introduction
Wildfires in Alaska are often a topic for discussion. This is true not only
among rrre control personnel but also resource managers, scientists, and
laymen. It is a subject that everyone talks about with authority whether or
not they have participated actively in fire control.
There appears to be an ever increasing controversy on whether to control
or not to control wildfire in Alaska with an array of positions between. A
recent article in Science by Mark Oberle (15) is a good example of growing
dissent relative to possible ecological drawbacks of Alaskan fire suppression
policies. Wildfire is becoming increasingly important from both an ecological
and economical point of view. Environmental groups and the general public
are showing increasing interest and concern centered around the role of
wildfire in perpetuating the type of environment desired on one hand and in
the destruction and waste on the other.
The intent of this paper is to develop a perspective into some of the
quantitative aspects of Alaskan wildfires. The discussion will provide a more
or less common basis on which to view the role of wildfire in the northern
environment. Information is presented on both statistical-fact and statistical-
projection bases. The latter has been developed with data, comments, con-
cepts and ideas, both my own and those of others interjected throughout.
Perhaps this paper will stimulate thoughts toward a new outlook by which to
view the entire subject of wildfire and its place and problems in the northern
environment.
Richard J. Barney
Pacific Northwest
Forest and
Range Experiment Station
Forest Service, U.S.
Department of Agriculture
51
-
l ' F
-E '-
52
Historical Information
It is conceivable that lightning as an ignition source and fuels to produce
fires have been present in the taiga since the glacial epoch. The problem is in
determining how long and how much wildfire has been present in this region
and if it was present in any abundance before man arrived upon the scene.
Although evidence is relatively sparse, it would appear that aboriginal man
played an important part in the cause of historical fire in the northern
regions (12). This early use, in conjunction with camping, signaling, hunting,
combating insect pests, and other applications, led to numerous wildfires. In
general, aboriginal man was quite careless with fire. Apparently, whenever
the weather was warm and dry, either man or lightning could start fires in
the taiga.
The problem increased with the coming of civilized man. This "newcomer"
to the northern country was perhaps more careless with fire than was the
native. The modern man's reasons for fire use were much the same as the
aborigines. However, several new reasons for fire use were added to the list
such as land clearing, forage production for livestock, and mineral explora-
tion activities. The addition to the native population already in the country
increased total number of ignition sources and fire starts. With no organized
fire control in this period of settlement, more and more country was being
burned at a faster rate than before. Much land was being reburned. This
changing pattern of frre occurrence resulted in a changing pattern through-
out the landscape. At the turn of the century or slightly earlier, 1890-98, the
period in which gold was discovered, fire activity increased as thousands of
men and women came north to seek their fortunes.
Although formal fire records as we know them today were not kept
before the 1940's, it has been reported that several thousand acres of forest
land were burned as a result of mining and exploration activities. During the
period, 1893-1937, in excess of 6,100,000 acres were reported blackened by
just 19 individual frres (11). It has been stated that an average of at least 1
million acres was burned each year from 1898-1940. In 1940, the Alaska fire
control service was organized (1 0). In light of subsequent statistical informa-
tion, the preceding acreage burned figure appears to be conservative. During
the first decade of organized fire control action, more than 1.2 million acres
were burned per year on the average. Because detection was basically limited
to accessible roads, this figure could be conservative too. In any case, an
average annual burn for the 1900-40 period of 1.5 to 2.5 million acres seems
more reasonable than the previously accepted 1-million-acre figure.
Wildfire statistics are available and have been compiled for the period of
1940-69 (2, 3, 6). The average annual burn for this period is approximately 1
million acres. Man still plays an important part in the fire history of this
country. On a 30-year basis, slightly over 70 percent of the fires have been
man-caused, and these same fires have burned 22 percent of the acreage.
Figure 1 shows these data graphically. The annual number of fires seems to
show a generally climbing trend, but annual burned acreage appears to be
decreasing.
-~-----~--~--------------~------~~-~---------~-
(I)
LLI
0:::
IL
IL
0
0:::
LLI
m
~
~ z
500
400
300
200
100
-NUMBER OF FIRES
-·-······ACRES BURNED
.
1
l !i .. .. .. .. .. .. :·
1\ I/ ~l !/'\ .
5.0
.
4.0
3.0
2.0
1.0
...... , .. · \:: :: ·.. ' 0----~~----~--------~--~'--~\~-~ .. ~~~----~
1940 1945 1950 1955 1960 1965 197 0
Figure I.-Number of f.tres and acres burned by year, interior Alaska, 1940-69.
C/)
LLJ
a::: u
<(
lL
0
C/) z
0
..J
_J
l:
The increase in number of fires over the past 30 years is in part due to the
increased activities of man in this country as well as improvements in detec-
tion and reporting of fires. In the early days of organized fire control,
suppression activities were generally limited to access via railroads, highways,
and waterways. The apparent trend in reduction of acreage burned is un-
doubtedly a direct result of improved detection and more aggressive sup-
pression action.
During the decade of the 1940's, 1,138 fires burned 12.4 million acres in
the interior of Alaska. The decade of the 1950's saw an increase in the
number of fires to 2,583, but burned acreage was reduced to approximately
10.7 million acres. The 1 0-year fire total for the 1960's was generally similar
to the preceding decade with 2,380 fires recorded. Acreage burned during
this most recent decade, however, took a significant drop to about 6.4
million acres. This acreage-burned figure was about half of the reported bum
of the 1940's. There has also been a decrease in the average size per fire by
decade with the 1940's recording 10,906 acres per fire; 1950's, 4,137; and
the 1960's, 2,674 (table 1 ).
Southeastern Alaska is not in the northern environment; however, a brief
mention of fire in this portion of the State should help to establish the role
of fire in Alaska overall. Although the records are not as impressive, coastal
Alaska also has a fire history. For the 12-year period, 1956-67, 243 fires
burned 5,403 acres.
--------~----~---~-------
53
54
TABLE I.-Number of fires and acres burned by cause and decade, interior Alaska, 1940-69
Lightning-caused fires Man-caused fires Total fires
Decade
Num-I Per-~ I Per-Num-I Per-1 I Per-Num-I I Acres
ber cent Acres cent ber cent Acres cent ber Acres per
fire
1940-49 200 17.6 Not available 938 82.4 Not available 1,138 12,4ll,076 10,906
1950-59 745 25.8 8,502,540 61.8 1,838 74.2 2,183,050 38.2 2,583 10,685,590 4,137
1960-69 853 35.1 4,801,563 71.7 1,527 64.9 1,563,482 28.3 2,380 6,365,045 2,674
1940-69 1,798 29.5 13,304,103 1 78.0 4,303 70.5 3,746,532 1 22.0 6,101 29,461,7ll 4,829
1 1950-69 only; data for 1940-49 missing.
Man is the primary cause of fire in the coastal Alaska area. Only four of
the total fires reported were lightning-caused, and these combined burned
only 1 acre. The man-caused fires were, for the most part, caused by local
residents (14).
Even though recent records indicate relatively limited fire activity in
coastal Alaska, especially from Cordova south or southeastern Alaska, fire
has been present in the past. Several old fire scars are evident on the land-
scape indicating that fires in excess of several thousand acres have burned in
the past. Charcoal deposits have been found throughout the area substantiat-
ing large fires in years gone by. Although fire is not presently a concern in
the area, current and projected harvesting activities may influence conditions
to such a point that fire will again play a more active and important role in
south coastal Alaska.
IMPACTS OF FIRE -KNOWN
Aside from numbers and acres, fires have had impacts on Alaska which
can be translated into some type of quantitative terms. Wildfire-related costs
and values in Alaska are high. Total presuppression and suppression costs for
the 1960's were about $40 to $45 million. The current-day market value and
replacement costs for fire control improvements, supplies, and equipment in
Alaska are estimated at $15 to $20 million. As the fire control organization
grows and becomes more sophisticated, using today's technology, the costs
also grow.
During the 1970 fire season, wages in excess of $3.6 million were paid to
emergency firefighters in Alaska. In addition, 17 aircraft were under con-
tract, nine for detecting fires and eight for spraying retardants. Initial attack
crews were supported with 17 helicopters. Twenty-five native villages sup-
plied thirty-six 25-man trained crews. This new and improved initial attack
and detection method resulted in a relatively small seasonal loss (4).
~
Losses in the interior have been calculated, using a figure of from $1 to
$16 per acre burned. These figures were for timber, seedlings and saplings,
watershed, recreation, range, wildlife, and other values. Improvements lost as
a result of wildfrres are generally considered at their current appraised
market value. On this basis, the 1969 fire season has been estimated to be
responsible for losses in excess of $16 million.
Some of the indirect impacts of wildfire can also be important. The
interior depends very heavily upon air transportation, and smoke conditions
are quite important. For example, during the 1969 season, one Fairbanks air
taxi operator reported that severe smoke conditions, a result of numerous
frres in the State, caused him to lose flying business worth $30,000-
$50,000. During that same season, several of the "bush" airfields were
officially closed because of the smoke conditions. The tourist business also
was affected by the poor visibility conditions. An actual measure of the
impact on tourism is impossible to obtain at this time.
Fire suppression efforts were responsible for saving considerable amounts
of real property in 1969. Had no control action been taken on the Kenai
Moose Range fire, known as the "Swanson River Fire," it is generally con-
ceded that hundreds of homes and other installations would have been
destroyed in the Kenai-Soldotna area. The exact number and value saved can
only be speculated.
Fire control operations in the State have essentially excluded wildfire
from urban and other areas within easy reach of fire control centers. Al-
though a few exceptions exist, wildfire of any magnitude is seldom seen by
the general public in urban areas of Alaska today. This general exclusion of
frre in urban and rural areas could well be causing more problems than it is
solving. Fuel complexes without fire may build to such a point as to make an
extremely dangerous condition. Time will tell.
IMPACTS OF WILDFIRE-SPECULATED AND PROJECTED
Because there are so many unknown ifs connected with Alaskan wildfires
and related areas, it is necessary that much of the impact be speculated at
this time. Using what information we now have along with our best judg-
ments considering what has happened elsewhere, as well as adjusting qasic
relationships, we can make some very reasonable projections and assump-
tions. Basic physical laws and other established relationships are generally
applicable here. Essentially, the problem is to supply the right numbers
locally to use in the general formula.
When the previous statistics are considered, it seems quite possible that at
least 100 million acres, an area the size of Montana, has been burned during the
70 years since the turn of the century. Let's assume that 25 percent of this
acreage constitutes reburning of land since the 1900 date.lf this is an accepta-
ble estimate, although probably conservative, then 75 million virgin acres
burned in the 70-year period. At this rate, we can speculate that the vast
majority of interior Alaska has been burned over within the past 200-250 years.
t
E
55
56
This time period could possibly be too long when we consider normal species
rotation ages, white spruce-1 00-150 years; birch-80-1 00 years; aspen-60-80
years; and the reported stand-age compositions in the interior ( 7). Some areas,
of course, would have been untouched by fire for longer periods, in some
cases over 325 years (5), but these are a very minor portion of the total land
area; however, these areas may represent a major portion of the high produc-
tion sites, i.e., river bottoms.
The most recent figures on commercial timber volumes in Alaska ( 7)
indicate that 14.8 billion cubic feet are located in the interior. Approxi-
mately 22.5 million acres of the interior region are classed as commercial
timber acreage, which means they produce a minimum of 20 cubic feet of
timber per acre per year. The average volume per acre of commercial timber
is about 658 cubic feet. A study of fires during a relatively recent 5-year
period indicates that about 5 acres of commercial forest land are destroyed
for every thousand acres of forested land reported burned (1). Distribution
of fire by cause and cover or vegetation type (2) and statistics for acreage
burned (3) indicate that about 52 percent of wildfires burn in forested lands
(table 2). Using some quick arithmetic, the 1 00-million-acres-burned figure
projected earlier7 and the preceding information, we can calculate and esti-
mate that over 171 million cubic feet of total volume has been destroyed
since the turn of the century. It should be kept in mind that this figure does
not include other fiber loss which falls outside of total volume and growing
stock definitions. These categories essentially consider all sound volume up
to a 4-inch top. As can be seen, there will be a considerable fiber volume
falling outside the limits of a 4-inch top in Alaska's interior.
TABLE 2.-Projected acreage burned by cause, percent, and cover type for period
1950-69 1
Lightning-caused Man-caused All
fires fires fires
Cover type
Per-Acres Per-Acres Per-Acres
cent cent cent
Conifer 36 4,789,477 36 1,348,751 36 6,138,228
Conifer-
broadleaf 11 1,463,451 27 1,011,564 14 2,475,015
Broadleaf 8 299,723 2 299,723
Tundra 51 6,785,093 15 561,980 43 7,347,073
Other 2 266,082 14 524,514 5 790,596
Total 100 13,304,103 100 3,746,532 100 17,050,635
1 Percent distribution by cause based on 1961-65 data (2) and applied to 1950-69 total acreage
figures by cause (3) to project acreage by cause and weighted total acreage and resultant percents.
-----------------------------------------------------------
Considering the acreage of the entire interior and the acres currently in
white spruce production, one might speculate that we would have much
more of this type if it were not for fires. Although good upland white spruce
sites are available, and some do maintain remnant spruce stands, the majority
of spruce is found in river bottoms where burning conditions may be less
severe. Repeated fires have converted many of the spruce areas to birch and
aspen stands (9, 13). Since white spruce is currently the most desirable
species commercially, perhaps wildfire should be excluded from the high
production, existing, and potential spruce sites.
Recent work on river-bottom sites in interior Alaska indicates that lack of
fire in white spruce stands may well cause site degradation. As the stands
grow older, a thick moss insulating mat develops which results in a lowering
of the soil temperature regimes. Eventually, a permafrost layer develops
making site conditions less favorable for white spruce (17). Therefore, one
might speculate that, under some conditions, fires can increase site quality
and production by destroying the insulation moss and organic layer.
Wildfires have both beneficial and detrimental effects on wildlife. The
exact effect depends on the species and the management objectives which
are under consideration. Fires can be beneficial in creating good range for
moose under proper burning conditions (16), but they can be detrimental to
the lichen winter range of the caribou (8). Determination of fire's position is
essentially a problem of individual perspective and overall planning goals.
In my opinion, we now have the technical capability to completely ex-
clude wildfire from the interior of Alaska. If our fire control capabilities
were equivalent in numbers, dollars, equipment, etc., on a per-acre basis to
the Western States, we could probably do the job now, especially if we were
to develop the intensive organization such as can be found in southern
California. To take action such as this may not be what we want-we may be
creating a worse problem than we are solving. We have to ask ourselves if we
want to maintain the landscape as is, allow climax vegetation, or what do we
want. When these questions are answered, we can determine the place of fire
in the environment of the north.
Summary
There is an urgent need to describe and quantify impact and effects of fire
beyond the numbers and acres previously discussed. We must be able to do
better than just speculate on what the various ramifications are. The eco-
nomic values and considerations are also required. Where dollar values are
not adequate, indexes must be developed. Fire and its role in the northern
ecosystem must be placed in the proper perspective in terms of the econ-
omy, the ecosystem, and the management objectives. Perhaps this meeting is
a start in the right direction.
-~-----------
~-
57
58
----------------
Literature Cited
I. Anonymous. 1964. Appraisal of fire losses in interior Alaska. USDA
Forest Serv. Pac. Northwest Forest & Range Exp. Sta., 10 p. (Unpubl.
office report on file in Juneau.)
2. Barney, Richard J. 1969. Interior Alaska wildfires, 1956-1965. USDA
Forest Serv. Pac. Northwest Forest & Range Exp. Sta., 47p.,illus.
3. . 1971. Selected 1966-69 interior Alaska wildfire statistics
with long-term comparisons. USDA Forest Serv. Res. Note PNW-154,
13 p., illus. Pac, Northwest Forest & Range Exp. Sta.
4. Bureau of Land Management, U.S. Dep. Interior. 1970. Alaska fire
report-1970. Alaska State Office. 25 p., illus.
5. Farr, Wilbur, A. 1967. Growth and yield of well-stocked white spruce
stands in Alaska. USDA Forest Serv. Res. Pap. PNW-53, 30 p., illus. Pac.
Northwest Forest & Range Exp. Sta.
6. Hardy, C. E., and J. W. Franks. 1963. Forest fires in Alaska. USDA
Forest Serv. Res. Pap. INT-5, 163 p., illus. Intermountain Forest &
Range Exp. Sta.
7. Hutchison, 0. Keith. 1967. Alaska's forest resources. USDA Forest Serv.
Res. Bull. PNW-19, 74 p., illus. Pac. Northwest Forest & Range Exp.
Sta.
8. Klein, David R. 1970. Tundra ranges north of the boreal forest. J. Range
Manage. 23(1): 8-14, illus.
9. Lutz, Harold J. 1950. Forest fires in Alaska damage more than timber.
USDA Forest Serv., Alaska Forest Res. Center Tech. Note 5, I p.
10. . 1953. The effects of forest fires on the vegetation of
interior Alaska. USDA Forest Serv., Alaska Forest Res. Center Sta. Pap.
I, 36 p., illus.
11. 1956. Ecological effects of forest fires in the interior of
Alaska. USDA Forest Serv. Tech. Bull. 1133, 121 p., illus.
12. . 1959. Aboriginal man and white man as historical causes
. of fires in the boreal forest, with particular reference to Alaska. Yale
Univ., Sch. Forest. Bull. 65,49 p.
13. . 1963. Early forest conditions in the Alaska interior-an
historical account with original sources. USDA Forest Serv. Northern
Forest Exp. Sta., 74 p.
-~-----------------·-·-~---
14. Noste, Nonan V. 1969. Analysis and summary of forest fires in coastal
Alaska. USDA Forest Serv. Pac. Northwest & Range Exp. Sta., 12 p.,
ill us.
15. Oberle, Mark. 1969. Forest fires: suppression policy has its ecological
drawbacks. Science 165: 5 68-571.
16. Spencer, David L., and John B. Hakala. 1964. Moose and fire on the
Kenai. Third Annu. Tall Timbers Fire Ecol. Conf. Proc. 1964: 11-33,
ill us.
17. Viereck, Leslie A. 1970. Forest succession and soil development adja-
cent to the Chena River in interior Alaska. Arctic and Alpine Res.
2(1): 1-26, illus.
. ··-···-·--···--···-~-
59
~--
~-
~
60
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
The natural role
of fire in northern
conifer forests1
Abstract
The primeval conifer forests of North America, with their associated
deciduous components, were largely fire-dependent ecosystems. Fire was a
key environmental factor in controlling succession, species composition, and
age structure of these forests. An almost universal policy of fire exclusion
over the last 50 years is superimposing a vegetation succession which is
"unnatural" and is often undesirable in terms of resource management. For
most forested areas, a fire policy is advocated which involves selective con-
trol of wildfires and managed, prescribed burning to duplicate the natural
fire regime.
Preface
This paper was originally delivered to the Intermountain Fire Research
Council at Missoula, Montana. But hopefully its theme is also relevant to
Alaska's forested interior, as well as to much of the interior of northern
North America. Lightning is now recognized as a major cause of fire in
Alaska. In fact, Barney's2 statistics show that lightning recently has been
responsible for most of the acreage burned. Thus fire must be viewed as a
powerful natural environmental factor in your ecosystems-and that is the
main thrust of my story.
There are some special circumstances in Alaska and the Canadian north
that deserve mention in this preface, however. In the northern environment,
organic layers gradually accumulate on soil surfaces on most physiographic
sites. This tendency is much greater in the far north than on comparable sites
farther south. Permafrost occurs on many sites as well. These facts raise
additional questions about the role of fire. For examplt:, what is the relation
of fire to peat accumulation and site deterioration? What is the natural role
of fire in the nutrient cycle of subarctic forests? Do fires retard peat accumu-
lation and recycle nutrients that might otherwise become permanently
locked up in organic layers? What is the relation of fire to permafrost?
1 Except for the preface, this paper is reprinted as originally presented at the Symp~sium, "The
Role of Fire in the Intermountain West," October 27-29, 1970, at Missoula, Montana; proceedings
published by the Intermountain Fire Research Council, 2705 Spurgin Rd., Missoula, Montana (illustra-
tions added for current publication).
2 Barney, Richard J. Interior Alaska wildfires 1956-1965. Portland, Oreg., Inst. N. Forest., USDA
Forest Serv. Pac. Northwest Forest & Range Exp. Sta., 47 p., illus., 1969.
Miron L. Heinselman
Principal
Plant Ecologist
North Central
Forest Experiment
Station
St. Paul, Minnesota
~
t r:
61
62
~~--~---·--~---~-----. ··-·-----·--------···---------~-------·-· '
Would fire exclusion cause increases in organic blankets and consequent
expansion of permafrost? What is the long-range role of fire in maintaining
the nutritional status of wildlife browse, lichen stands, berry crops, and
other plants upon which the northern fauna depend? You need answers to
these questions. I cannot supply many-but the questions are there, and they
are im,p ortan t.
I see one other circumstance worth noting. It is that so much of the
northern interior forest is not of value for timber. I know you have some
fine spruce and birch stands along the river valleys. But much of your forest
will probably never be exploited for pulpwood or sawtimber. Its chief value
may, therefore, lie in its function as wildlife habitat and as an esthetic
component of the northern scene. But if this is so, what about the role of
fire? Would fire exclusion alter the natural environment in ways detrimental
to these other values? If fire was part of these ecosystems for millenia, is it
not likely that the entire biota-plants and animals alike-were adapted to
some natural fire periodicity? These questions are relevant to noncommercial
forests and nature reserves everywhere, but they have special meaning in the
far north where such a high percentage of the forest is not exploitable. They
make research concerning the ecological effects of both fire and fire exclu-
sion even more important than in regions to the south. The alternatives and
the values involved are quite different.
With these qualifications, perhaps the balance of this paper will be in
context for my new far-northern audience. At least I offer it to you for what
it is worth!
THE NATURAL ROLE OF FIRE IN NORTHERN CONIFER FORESTS
by Miron L. Heinselman
The primeval conifer forests of northern North America and their associ-
ated broadleaf elements were mostly fire-dependent ecosystems. By this I
mean that fire was the key environmental factor that initiated new succes-
sions, controlled the species composition and age structure of the forests,
and produced the vegetation patterns upon which the animal components of
the ecosystem also depended. This was certainly true of the forests of
northern Minnesota and adjacent Ontario where my current forest history
studies and those of Spurr (5) and Frissell (3) apply. I am convinced it was
also true of most forests of the Intermountain West (the concern of this
symposium), the Rockies, the Pacific Northwest, the Canadian and Alaskan
boreal regions, and the Sierran region of California. I base this conclusion on
a large body of forest history and autecological literature, and on personal
observations in much of the West and North. It is really only a hypothesis,
but its validity can be checked with field studies wherever virgin forests still
remain.
Fire was the great reaper that periodically eliminated or opened up old
forest stands, making way for new generations of trees. The primeval land-
scape was a vast mosaic of stands in various age classes and successional
------------------------------------------
stages following fire, interspersed with recently burned areas. Younger stands
often had dense, relatively pure, even-aged overstories of such post-fire
pioneers as jack pine, lodgepole pine, black spruce, quaking aspen, western
larch, or Douglas-fir. Even the mature forests usually had individual trees in
the overstory that dated from the last fire. Succession may have greatly
modified the composition and structure of these old stands, but the over-
story trees may still have been primarily from the first generation after fire.
Indeed, this is still true of the virgin forests today, after 50 years of protec-
tion from fire. With the longer-lived post-fire species, such as the red, white,
ponderosa, and sugar pines, western larch, Douglas-fir, redwood, and
sequoia, this first generation can last many hundreds or even thousands of
years.
Other forests probably had a stand structure consisting of distinct groups
or groves of trees, with the individuals in each group dating from a particular
burn that had opened up the old forest at that time. Red pine, ponderosa
pine, giant sequoia, and other forest types often exhibit such a structure.
True climax forests of shade-tolerant trees that perpetuated themselves for
several generations in the absence of fire were probably uncommon. Such
stands did and still do exist, but in most regions I suspect they occurred only
on those unusual physiographic sites where fires are rare.
Fire scars on "veteran" trees in our remaining virgin forests still testify to
this long history of fire. Charcoal occurs almost universally in the soil pro-
files of the virgin conifer forests of many regions. And many stands have
ancient, charred snags still standing among the present generation of trees, in
silent testimony to the forces that brought about their origin.
We have known many of the facts of fire ecology for a long time. If you
doubt this, try reading Frederick E. Clements, "Life History of Lodgepoie
Burn Forests" (1). (As an aside, I must note that Clements found stands
dating from 1864 to be the most abundant in his Colorado study, just as I
have for the Canoe Area in Minnesota, 60 years later!) What has been lacking
so far is not relevant research, but the simple recognition that fire is part of
the natural environment-that fire is not an unnatural disturbance, and that
whole ecosystems have evolved in response to it. We have focused ecological
studies on succession to climax and on the identification of climax com-
munities, and neglected the much more prominent "pioneer" and early
"seral" stages. It is a paradox that Clements produced one of the first studies
of fire ecology and yet was responsible in large measure for our preoccupa-
tion with climaxes.
We have known for many years about the adaptations of certain trees,
shrubs, and herbs to fire-for instance, the serotinous cones of jack pine and
lodgepole pine, the suckering of aspens, the sprouting of birches, oaks, and
redwoods, the light wind-blown seeds of pines, spruces, aspens, willows,
birches, and alders, and the thick fire-resistant bark of ponderosa pine, red
pine, Douglas-fir, and redwood. Adaptations such as these must have evolved
through eons of existence in a fire environment. I will not cite specific
63
64
·---~-------------····----~--~----------· ----~
references, but details can be found in the Forest Service's Silvics Handbook
(2).
There is some direct evidence for the long-term presence of fire and fire-
adapted tree species in North America. Charcoal layers are common in peat
bogs in the north, and some of these layers in Minnesota have been shown by
carbon-14 dating to be 3,000 to 8,000 years old or more. A collection of
tree fossils from early glacial drift in Minnesota, carbon dated at more than
38,000 years old, contained cones and wood of jack pine and black spruce-
both common post-fire species. Some of the wood was charred (4).
Fire may aid the reproduction of trees in one or more of the following
ways:
(1) It may reduce competition for moisture, nutrients, heat, and light by
temporarily eliminating the overstory or understory trees, shrubs, herbs,
grasses, mosses, and lichens.
(2) It may create suitable seedbeds by exposing mineral soil or dense
ashes, where moisture and nutrient conditions are more favorable than in the
thick, loose litter and humus layers of old stands.
(3) It may trigger the release of large seed supplies (as in the case of the
serotinous-cone pines), or stimulate vegetative reproduction (as in the
aspens, birches, oaks, redwood, etc.).
( 4) It may release quantities of essential mineral elements needed for
plant growth. These elements are present in the ash layer, and represent a
recycling of nutrients accumulated in the litter, humus, wood, bark, and
foliage of the old forest.
Fire also played another role. As the principal agent that destroyed old
forests, it kept a significant proportion of each region in young stands. It is
well known that young stands are less susceptible to certain insects and
diseases, as well as to windfall. Fire must therefore .have had a "sanitizing"
effect by eliminating stands before these problems overtook them, by
"cleaning up" old blowdowns and insect-killed stands, and by keeping much
of the forest too young to support insect or disease outbreaks.
For example, in Minnesota and eastern Canada spruce budworm outbreaks
seem to require large concentrations of old fir and spruce. Such outbreaks
may have been less prevalent in primeval times than now, because fire would
have frequently curtailed the expansion of these shade-tolerant climax
species. Similarly, large stands of old lodgepole pine and Engelmann spruce
are very susceptible to barkbeetle attack. Again, fire may have prevented
such concentrations of old stands in primeval times. The barkbeetle
epidemics now rampant in the Rockies and the Intermountain West may be a
product of fire exclusion. Dwarf-mistletoe on black spruce, lodgepole pine,
and other species is another case in point. This parasite is temporarily
eliminated when fires remove its host. The host trees usually reproduce
easily after fire, but mistletoe does not. Thus fires can "rejuvenate" an old
mistletoe-ridden forest-and this was probably the natural check on this
----~· ---··--------
'· '· "
~-
parasite. With fire exclusion we are seeing a vast expansion of mistletoe.
The animal component of these forest ecosystems was also adapted to a
fire ecology. Some of our most abundant forest herbivores-deer, moose, elk,
snowshoe hare, and beaver-are best adapted to recent burns and early
successional stages of the forest-not to climax forests. When the forest
matures the open areas disappear, and the young trees, shrubs, and herbs
upon which these animals depend disappear. Predators such as the wolf,
cougar, fox, and lynx depend on these herbivores, and thus also on periodic
disturbance of the forest by fire. This is also true of the ruffed grouse and
many other forest birds. Thus the whole ecosystem-plants and animals
alike-was geared to periodic fire.
I do not mean to imply that there were no old forests. We know that
mature forests covered vast areas, and some of them were well along the
successional route to climax. But if we study the record, we will see that fire
seems to have been the principal natural agent that periodically set succes-
sions back. A random, but very real fire "rotation" insured that few stands
reached climax.
The conclusions just sketched out resulted largely from the forest history
studies that we have been conducting in the Boundary Waters Canoe Area in
Minnesota since 1966. Let me just outline what we have been doing there,
and some of the findings that are emerging. This is not the Intermountain
West, but the research methods and some of the ecological principles should
apply to your region.
The Canoe Area is a unique 1-million-acre lakeland wilderness-the only
large unit of the National Wilderness System east of the Rockies. Its present
forests are a complex of virgin pine, aspen, birch, spruce, and fir, covering
about 400,000 acres, and second growth on logged-over lands. The logging
between 1895 and 1940 removed primarily large pine; since then, logging has
been mostly for pulp on national forest and state-owned tracts. The goal of
our ecological studies is to provide a scientific base for possible future
management programs aimed at maintaining, and where necessary restoring,
the natural ecosystem, and to help management evaluate policy alternatives
and their consequences.
The impact of western man on the Canoe Country began with the fur
trade about 1670, but there were no permanent settlements on the
periphery, or lumbering, mining, and so on, until about 187 5. The present
virgin forests are mostly less than 150 years old, although some stands are up
to 370 years old. They escaped the early logging mostly because they were
too young. But they are just as pristine ecologically as the forests in our
western wilderness areas and parks-more so than some, because they have
not been grazed.
The objective of my forest history studies is to determine the origin and
ecological history of the virgin forests, and to relate their present status to
the primeval situation. We have now deciphered this history for about the
past 370 years. This was done by: (1) Checking available historical records,
---------------------·-----------------· ------------·---------------
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old maps, old government reports, and the General Land Office Survey
notes; (2) obtaining the ages of thousands of overstory trees on some 900
study plots scattered across the entire virgin forest and some recently logged
stands where remnants were present; (3) obtaining a fire chronology from
old fire-scarred trees by counting annual rings from the cambium to the
scars. This was done on wedges cut from the scars of more than 1 00 strate-
gically located trees; ( 4) mapping forest age classes and fire boundaries
throughout the area from these records with the aid of airphotos, forest type
maps, and field checks; and (5) studying the age structure and time of repro-
duction by species in 30 stands scattered across the area.
The following conclusions seem warranted, although they are tentative
until the final analyses and fire maps are completed:
(1) At least 80 to 90 percent of the virgin forests can be traced to a
post-fire origin. The oldest known stand dates from about 1595 A.D., and
the youngest stands of any size from the fires of 1936. Charcoal is almost
universal in soil organic layers.
(2) Major fires recurred at 5-to 50-year intervals from at least 1600 A.D.
to 1920. Some areas reburned at intervals as long as 200 to 300 years, others
as short as 10. One area may have last burned about 350 to 370 years ago.
(3) There may have been an increase in fire from 1800 to 1910 due to the
activities of local people, but this is still uncertain.
( 4) Since about 1920, only limited areas of virgin forest have burned, due
to effective fire control by the Superior National Forest. Fire is no longer an
active ecological factor.
(5) Most stands still have a nearly even-aged overstory dating closely from
the last fire. Some stands of red and white pine and other species contain
groves or scattered trees of two or more age classes, each dating from sepa-
rate fires. Some sites regenerated slowly and contain a mixture of tree ages.
(6) The areas burned most frequently or intensely are large uplands more
distant from natural firebreaks. Jack. pine, black spruce, aspen, birch, sprout
hardwoods, and fir dominate such areas.
(7) The areas Jmrned least frequently or intensely are sites naturally less
subject to fire, such as swamps, ravines, lakeshores, the lower slopes of high
ridges, islands, and the east, north, northeast, and southeast sides of larger
lakes or streams. White pine, red pine, white spruce, and northern white-
cedar are relatively more abundant on such sites.
(8) It is likely that fire was frequent enough in this ecosystem to prevent
succession from proceeding far ·toward the theoretical spruce-fir-birch
climax. Most forests today are only first generation stands following fire, and
this may always have been true. Even the oldest stands still do not meet the
test of self-reproduction without fire, because the oldest individuals still date
from the last fire. The lifespans of red and white pine, the spruces, and cedar
(300 to 500 years) seem longer than the probable periodicity of fires on
---~~------~------
most sites. Even jack pine and aspen can persist for more than 200 years
without fire, and few areas escaped longer than this. Thus, understanding the
natural vegetation is more a question of the selective regeneration of species
after fire, and of post-fire successions, than of understanding a hypothetical
climax that might have developed in the absence of fire.
(9) The vegetation that might develop with fire exclusion (present
practice) is in a sense unnatural, and largely unknown to science. We do not
know whether such circumstances have occurred in post-glacial times, and
we have no good examples of climax forest today.
How many of the fires in this 370-year period were caused by white men
or Indians, and how many were caused by lightning? Lightning was and still
is a major cause of fire, but we can be sure that many fires were man-caused.
The real question, however, is not the specific cause of ignition for each fire
(which can never be determined anyway), but whether the pre-white man, or
possibly even pre-Indian, fire regime differed in a major way from that I have
described. What we really want to understand is the natural fire regime under
which the biota developed.
Fortunately the means may be at hand to do just that! A cooperative
study is underway with the University of Minnesota Department of Botany
and the University Limnological Research Center to determine the sequence
of vegetation changes and the associated fire history for nearly the full
post-glacial time period.1 This is possible because annually laminated organic
lake sediments have been discovered in the Lake ofthe Clouds-a small, deep
lake far within the virgin area. Sediment cores have been collected, and the
full post-glacial record is present. There are some 9,500 annual layers of
sediment (lake mud)-checked by carbon-14 dating. The sediment contains
tiny bits of charred wood and plant fragments, as well as the usual plant
pollens and other fossils.
By studying the fluctuations in abundance of charcoal and of various
plant pollens, the University research team hopes to eventually document
the vegetation and fire history of the locale for 9,500 years. By relating
fluctuations in charcoal in the upper sediments to our tree ring records of
fires near the Lake of the Clouds, it is expected that major fire years can be
identified. The work is tedious, and it will take time and more research
support to complete this project. Eventually other lakes will also be studied.
But already the project has changed the questions we are asking. The
question is no longer, "Was fire a natural factor before the white man
came?" It is now, "How much fire was natural, and were there changes
associated with the buildup of human populations, with the arrival of white
men, and with post-glacial climatic fluctuations?"
If you accept in broad outline the picture of the natural role of fire I have
just drawn, then what are its implications for wildland management? For
silvicultural purposes we had at least better take another hard look at pre-
1 Drs. H. E. Wright, Limnol. Res. Center, and E. J. Cushing, Dep. Botany, Univ. Minn., direct this
research with the aid of Albert Swain, Alan Craig, and Steven Anthony.
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scribed fire as a tool in obtaining regeneration. It is nature's way.
But for Wilderness Areas , National Parks, Research Natural Areas , Wildlife
Management Areas, and a variety of other non-commercial forest lands, the
implications are far-reaching. First , for a ll areas where preservation of
natural ecosystems is an important public goal we must learn to understand
the role of fire, and then provide for that role as expeditiously · as possible.
The present nearly universal practice of fire exclusion is a very powerful
form of vegetation manipulation. And it certainly is not likely to result in
ecosystem preservation where the original natural plant and animal com-
munities were fire-dependent. In fact, at present we are inadvertently
committing such areas to a grand ecological experiment. We are trying to
produce climax communities over an entire landscape , in areas where such a
situation probably never existed in nature. Even ecologists cannot foresee
the consequences .
One possible consequence is a gradual a ccumulation of fuels -leading to
the potential for a conflagration if a wildfire finally does escape during
extremely dry conditions. The extent to which fire exclusion will influence
fuels through the changing forest age classes, vegetation types, and stand
conditions is a serious matter that deserves study. Both standing fuels and
accumulations of down timber, litter, duff, and humus should be considered.
Collaboration of fire scientists, ecologists, entomologists, pathologists, and
other specialists will be helpful if projections of fuel conditions into the
future are attempted.
Only six fire policy alternatives seem available to managers-ofwilderness
areas, parks, and related nature reserves. Failure to consciously pursue a
policy will still result in some combination of these options. The options I
now see are:
( 1) Attempt fire exclusion and accept the slow but pervasive changes in
plant and animal communities that inevitably follow.
(2) Allow "safe" lightning-caused fires to burn; allow also for some other
wildfires that cannot be controlled, but extinguish the rest. If this option
results in less than the natural fire frequency and burned area, so be it.
(3) Allow "safe" lightning fires to burn, allow for some other wildfires
that cannot be controlled, but prescribe enough additional controlled fires. to
assure the natural fire regime.
(4) Suppress all wildfires to the extent feasible, and duplicate the natural
fire regime with prescribed-controlled fires.
(5) Allow all wildfires to burn unchecked unless life or property are
directly threatened, and hope that a natural fire regime will result.
( 6) Abandon the ideal of natural ecosystems and turn to full-scale vegeta-
tion and environmental manipulation by mechanical and chemical means,
seeding, planting, and so on. Attempt to produce desired vegetation with the
tools of applied forestry.
For most areas I favor either option (3) or (4), depending on the particu-
lar fire control, human safety, and property safety considerations of the
area. Either would provide approximately the natural fire regime and avoid
the risk of letting wildfires get out of hand before control is attempted.
The second option, allowing for "safe" lightning fires and some escapes,
but not using prescribed fires, may be acceptable where it would yield close
to the natural fire regime. In isolated mountain areas this policy may be valid
if there is little possibility of fires escaping to lands outside the wilderness or
park.
The last option, mechanized forestry, seems inconsistent with the basic
philosophy and objectives of our national parks and wilderness areas. How-
ever, it is urged as the only realistic and practical choice by some foresters
and by many of the forest industry spokesmen, who point out that a
commercial harvest of timber could be obtained as a byproduct. Timber
cutting is now practiced in parts of the Boundary Waters Canoe Area, in
' f-
E-
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Algonquin and Quetico Provincial Parks in Ontario, and in several other large
"parks" in Canada and other countries. But in none of the cases with which I
am familiar is there a serious attempt to duplicate primeval vegetation condi-
tions following cutting. Unfortunately, this option, without commercial
incentives, will have to be resorted to in some auto campgrounds and other
high-use sites.
I reject the fifth option, allowing all wildfires to burn, both because it
endangers life and property and because with recreational use the location
and frequency of fires would be unnatural. We cannot endanger human lives
either inside or outside wilderness areas, and we cannot risk damage to
commercial forests or to structures outside.
It is clear also that I do not favor the first option-attempted fire
-~~~~--~~ ~~~~--~~~ ~------
-~-.----------~~~~~
exclusion-except as an interim measure until the necessary expertise in
prescribed fire and wildfire management can be developed.
But I must emphasize that in most areas we are not ready to introduce
prescribed fires of the kinds required ecologically, or on the scale needed to
duplicate the natural regime. Much experimentation will be needed to
achieve technical expertise in firing and control methods, in gauging weather
and fuel factors, and in understanding the fire prescriptions necessary to
achieve the ecological effects of the natural wildfire regime. The size of areas
to be burned, the frequency of burning, and the burning techniques all
require research. There is no need-and indeed it may be impossible-to burn
every year. One might allow or prescribe major burns only once every 10 to
20 years. This will depend on the natural fire frequency as well as on burning
weather. ·
There has already been much research in prescribed burning, and many
applications are being made. But for ecosystem applications in the virgin
wilderness, I am talking about the introduction of severe ground fires, or
even running crown fires in mature forests. In some cases these fires must be
severe enough to kill most or all of the trees within the burn. Of course, only
a small percentage of the park or wilderness would be burned at any one
time. The aim would be to slowly re-establish the primeval distribution of
forest age classes and vegetation stages. We have little relevant ~xperience
with prescribed burning to achieve this.
Research to develop the needed expertise in both prescribed burning and
fire ecology is now underway adjacent to the Boundary Waters Canoe Area
and in Sequoia-Kings Canyon National Parks. These studies are new, and
much more work is needed in these and many other areas. The enthusiastic
cooperation of resource managers, ecologists, fire behavior and prescribed
burning specialists, meteorologists, and equipment development experts will
be needed to bring prescribed burning for ecosystem management to the
operational stage.
We must expand our knowledge of the ecology of many species of plants
and animals in a fire-influenced environment-some of this work can be done
effectively in conjunction with prescribed burning research. We also need
studies of the history of natural ecosystems in many more areas if we are to
evaluate present conditions and determine appropriate goals for preservation
programs. And baseline inventories of plant and animal communities will be
needed in each area if we are to understand and document the effects of
future programs.
I would be remiss if I failed to mention one more need-the need to
develop public understanding and support for ecologically sound resource
programs in wilderness areas and national parks. There is plenty of support
for preservation in the abstract. But the public needs the unvarnished facts
about natural ecosystems, and about the measures that will be needed to
restore and maintain these systems. At present there may be a problem with
understanding the need for reintroducing fire-a legacy from 40 years of
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72
~~~ ----
intensive fire prevention campaigns. This problem prevented our carrying out
an otherwise feasible experimental burn just this past August.
I think the public will understand, and will support such research if given
the facts. A start has been made-note the several recent articles in Audubon,
National Parks Magazine, Naturalist, and even True magazine. More will be
needed, including radio, TV, and press releases, if we are to offset the mis-
conceptions now in the public mind.
But fire was part of the nature for eons; and mankind has lived with fire
on the landscape since his earliest days as a primitive hunter. The need to
retain some examples of the earth's primeval ecosystems is real and urgent.
The educational, scientific, and cultural values of such areas will be im-
measurable in the man-dominated world we shall soon find ourselves living
in. Those of us pursuing careers in fire management, fire behavior research,
fire control research, prescribed burning research, or fire ecology have a
special opportunity-and a special obligation.
Literature Cited
l. Clements, Frederick E. 1910. The life history of lodgepole burn forests.
USDA Forest Serv. Bull. 79, 56 p.
2. Powells, H. A. 1965. Silvics of forest trees of the United States. U.S. Dep.
Agr. Handb. 271, 762 p.
3. Frissell, Sidney S., Jr. 1968. A fire chronology for Itasca State Park,
Minnesota. Univ. Minn. Forest. Res. Note 196.
4. Heinselman, M. L., and E. I. Roe. 1963. A record of some Pleistocene
trees and shrubs from Itasca County, Minnesota. Forest Sci. 9: 336-337.
5. Spurr, Stephen H. 1954. The forests of Itasca in the nineteenth century
as related to fire. Ecology 35(1): 21-25.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Fire
in park
management
Abstract
Most of the existing Alaskan State and National Parks were established to
provide for human enjoyment of the natural features and to preserve the
area in its natural condition. The natural condition is identified as that
occurring before the effects of white man's influence became noticeable. The
natural condition is not a single year but represents changing ecological
conditions over a long period of time.
In many Parks, fire was an important ecological factor operating to main-
tain the area in its natural environment.
After State and National Parks are created, one of the first management
goals to be put into practice is the suppression of all wildfires.
This suppression of fire, however, results in the development of an
unnatural environment, at least in those areas where fire was a natural factor.
Probably the most efficient, inexpensive, and natural way to reestablish
the natural environment is with prescribed burning.
Purposes of Parks
State and National Parks are established to protect their outstanding
features and to provide for human enjoyment of these features in a manner
that will not destroy or impair the features and values to be preserved. In
some areas, historical remains are the main reason, but in others, including
the three State parks, one National Park, and two of the three national
monuments in Alaska, the natural features are the reason for establishing the
park. This paper is concerned with those natural features, primarily biotic in
origin, that are affected by fire.
The natural biotic features are identified as the environmental conditions
or state that existed prior to white man's arrival on the scene in sufficient
numbers to noticeably affect the natural ecology. For the interior of Alaska,
this would be before 1898, although there are probably enclaves where
man's influence is just now beginning to be felt.
Joseph E. Hoffman
Institute of Social,
Economic, and
Government Research
University of Alaska,
College, Alaska
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~-
This natural environment that existed prior to white man's arrival cannot
be thought of as a given year, such as 1897, but must be considered as a
continuum of a continually changing environment over a long period of
time. Many ecological factors operated to change this natural environment;
for some areas, a very important one was fire, either started by lightning or
set by aboriginal man. Historically then, some park areas have probably
never experienced a wildfire in the past I ,000 years. Other areas may have
had fires on an average of every 5, I 0, 50, or I 00 years.
Effects of Fire
Fire can have a very dramatic effect on plants and animals. The effects of
fire, however, are as varied as the species it affects and the conditions under
which it occurs. Differences in topography and burning conditions can
rapidly shift a fire from a creeping fire, barely able to perpetuate itself, to a
raging inferno.
The temperatures produced in any given fire along with their duration are
probably the most critical characteristics. A hot, slow-moving ground fire
may kill all vegetation and burn all the organic matter down to mineral soil.
This type of fire is extremely destructive, possibly setting the ecological
succession cycle back to one of the first stages and creating conditions for
massive soil erosion.
A mild, fast, surface fire, however, may burn the dead fuel but destroy
little live vegetation and thus have only limited effect. Only when fires have
low to moderate intensity and shorter duration can the ability of different
species to withstand fire influence their survival. The giant sequoia trees with
their thick bark to act as insulation can survive fires that will kill other tree
species. Age also plays a role in the survival of woody species. Young trees
and bushes are usually more susceptible to fire damage than older ones.
The different degrees of fire intensity and duration along with the various
types of plant species result in different effects as shown by plant regen-
eration, disease and insect occurrence, watershed changes, and future wild-
fire damage. It is widely recognized that some species of trees, such as
Douglas-fir, various pines, aspen, and birch that today cover vast acreage, owe
their origin to old fires' preparing a suitable seedbed. In many grasslands, the
gradual colonization by woody species is retarded or reversed by fire since
most grasses can regenerate after a fire better than woody species.
Disease and insect buildups may follow damaging fires since the dead and
injured plants are suitable hosts. Generally this buildup only lasts a few
years, but it may be sufficient to kill plants that survived the fire.
Intense wildfires can result in soil erosion, but mild fires may have very
little effect. The amount of duff or humus remaining after a fire is a good
indication of the degree of soil damage-the more duff remaining, the less
the damage. Fire that favors grasses over brush may actually reduce erosion
by providing a better ground cover.
-~~----------------
In areas where brush is extremely dense, the material killed by fire, but
not consumed, may exceed that removed. This sets up conditions where a
subsequent bum may be more destructive than the earlier one.
Past Park Management
The "era of preservation" started with the establishment of Yellowstone
National Park in 1872 and reached a peak with the establishment of the U.S.
Forest Service and National Park Service shortly after the turn of the cen-
tury. In part, this was a reaction against the excesses of the "era of exploi-
tation" and a realizatlonfhaiour renewable natunil assets are not inexhausti-
ble. The establishment of parks usually brought about an intensification of
effort for the control of wildfire. Since then, there have been enough examples
of extremely destructive wildfires to provide impetus to increased fire sup-
pression activities.
Increasing technology through mechanization has led to more effective
fire control, and the acreage burned by wildfires has been gradually reduced
over the years. The development of the Bureau of Land Management's initial
attack crews, often led by smokejumpers, is an example of efforts being
made to stop wildfires. Along with increasing technology has come the
public relations effort characterized by "Smokey the Bear." Our society is
continually reminded that wildfires are bad and that every citizen has to be
careful with fire.
The general success of the wildfire suppression activities has produced
subtle changes in the environment. With the exclusion of fire, fuel continued
to accumulate, whereas the more frequent wildfires of the past had kept this
to a minimum. Now when a wildfire does occur, it may have many times the
amount of fuel as in the days before fire control, and the destructive force
may be greater.
An example of the potential danger resulting from this subtle change is
found in Sequoia National Park. There, frequent wildfires in the past had
kept fuel quantities low so the heat generated did not damage the mature
giant sequoia trees. Today, the understory of white fir and sugar pine
presents a threat to the survival of some of the big trees if wildfire should
occur.
The other subtle change in the environment is manifested in changes in
the ecological communities found in a park. Many plant communities owe
their particular composition by species and age to the effects of previous
wildfires. Many parks at the time of establishment were a mosaic of various
types of plant communities, each having been influenced in some way by the
absence or presence of past wildfires.
Today, with fire suppression, plant communities follow the slow change
toward the climax community for that site. Where once fire would have
slowed or set back the successional process to a more primitive stage, we
now have a trend toward uniformity as represented in the climax stage.
Historically, the area never may have reached the climax vegetation stage.
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76
Our objective of keeping the area in its natural condition has not been
attained. Instead, we have provided conditions for the development of an
environment that never may have existed before in that area. To the average
tourist, the area still looks natural, but some of the variety of the original
environment has been lost.
Future Park Management
One of the important considerations for future park management is the
recognition that fire has been, in many areas, a dominant factor in the
ecology of the park. The analysis of the past role of fire will require the
careful and objective evaluation of the evidence of fire activity. This analysis
should include the effects of man on fire occurrence, primarily his fire
suppression activities, and to what extent restoration is feasible.
Answers need to be found for such questions as how often did fires occur,
and what were the effects of these fires. The answer to the question of what
plant communities or ecosystems existing today owe their origin, at least in
part, to fire will also give us clues to the importance of fire as an ecological
factor. This will be a difficult task, given the interrelationship of fire in the
natural ecology and the void of data on some species not of economic
importance. Some answers may never be found. It will require maps showing
vegetative types and the locations of old burns and the collection of data on
the interrelationship of fire on the ecology of plant communities. If possible,
the ecological role of fire should be determined for all major species or at
least their major communities.
A second consideration for future park management is the development of
a policy recognizing that fire can and should be used as a tool for the
management of a park in its natural state since it is probably the most
efficient, inexpensive, and natural tool available. This is not to imply that
wildfires should be allowed to burn, since these fires usually pose too great a
destructive threat. A policy of fire for park management is a realization that
at certain times and places the beneficial effects of a fire outweigh the
negative effects. This management use of fire is called prescribed burning. It
is the skillful application of fire to fuels under conditions of weather, fuel
moisture, soil moisture, etc. that will allow confinement of the fire to a
predetermined area and at the same time will produce the intensity of heat
and rate of spread required to accomplish certain planned benefits. The
objective is to employ fire scientifically to realize maximum net benefits at
minimum damage and costs.
After a fire management policy is accepted, the next step is the develop-
ment of an ecologically sound and carefully thought out fire management
plan. This plan should be tailored to the ecological needs of the ecosystems
within a park. It will focus attention on areas where fire is believed to have
played a major role in the development of an ecosystem. A fire management
plan is part of a general resource management plan and must reflect interrela-
tionship with other management plans.
.-----~------------~------
The fire management plan should indicate if and for what purpose pre-
scribed burning should be used to restore or maintain natural conditions
with a minimum of overt effort by man. This will include the identification
of the "natural" state desired and the method to obtain this objective. It is
based on the evaluation of effects of past fires. However, in the absence of
any indications of past fire effects, prescribed burning should not be used.
Another part of the fire management plan will be park maps zoned by
aspect, degree of slope, and vegetative type. A correlative index with the
base fire' danger station is needed for each zone. Eventually, we need an
accurate prediction of fire behavior under different conditions for each zone.
We should recognize that it will be impossible to use prescribed burning
under conditions as they existed 1 00 years ago. Parts of the park with high
human values, such as a campground, should not be burned. Nor should the
entire park be subject to prescribed burning at one time due to the destruc-
tion of esthetic values.
The fire management plan also needs to consider hazard reduction as an
objective of park management. This is the reduction of fuel by prescribed
burning, and its purpose is to lower the destructive effects of a wildfire
should one occur. It can play an important role in creating a buffer zone of
lower fire danger around high risk areas such as picnic areas, campgrounds,
and other developed areas.
The last step of a fire management plan is implementation. This will
require trained specialists, experienced in the skillful application of all the
data available to insure a successful burn. Experience in fighting fires is not
enough. The men in charge must know with reasonable accuracy the effects
of a fire under given situations. The specialist must understand that no one
factor by itself is controlling, and he must consider all factors in composite.
In some cases, he will need to develop techniques for achieving the desired
results. But until such time as the effects of fire can be predetermined,
prescribed burning should not be practiced.
Another factor the specialist must consider are the tools available to
control the prescribed burn in park areas. Heavy equipment may not be
allowed. Possibly only men with shovels will be permitted to guide a pre-
scribed fire. It is entirely possible that the right conditions for a successful
burn may occur only during certain seasons of the year and then only for a
few days or a week or two.
An important function of future park management will be a public rela-
tions effort to explain to the public the reason for and need to use pre-
scribed burning as a tool. The fire suppression programs such as "Smokey
the Bear" or "Keep Alaska Green" will need to be modified. The public
should understand that some fires, set by and under the control of experts,
are good and produce a better, more natural environment. It should be
stressed that prescribed burning will not destroy all vegetation and will be
confined to a predetermined area.
77
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78
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To provide guidelines to the public relations program, we need to know
how the general public views a burned area. When an area is blackened by
fire and vegetation has not yet returned, the public probably considers the
sight a disgraceful waste of natural resources. But once vegetation has re-
turned and the charcoal look has worn off, then what do people think? How
many people can identify an area as having been burnt 1, 2, 5, or 10 years
later? Possibly land managers are more sensitive to fire scars than the general
public.
An imp_ortanLsid~ benefit of prescribed burning will be in the field of
outdoor education. The composition of plant communities before prescribed
burning and their response to it will be a fertile area of environmental
education. Prescribed burned areas may be excellent laboratories to illustrate
succession of plant communities and the factors that influence succession.
I am deeply indebted to David B. Butts for the many concepts and ideas
presented in his report. 1
1 David B. Butts. Fire for management in national parks. Unpublished Master of Science Professional
Paper on file at Colorado State University, Fort Collins, Colo. 134 p., 1967.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
National Park Service
fire policy in
National Parks
and Monuments
Richard G. Prasil
Abstract Management Biologist
National Park Service
The National Park Service has studied certain areas and intends to continu-Anchorage, Alaska
ally study other Parks. to determine whether or not natural fires will be
allowed to burn. It is understood by this Service where natural fires will
cause a threat to other land agencies, State or Federal, every effort will be
made to assist in the presuppression and suppression of same. Where human
life or high value areas are involved, fire suppression will be of prime impor-
tance. Human life and wildlife values will be of prime importance. Areas will
be evaluated and decisions made relative thereto.
Intensive studies will be undertaken within the next few years so that
demarcation of these areas can be made and management decisions can be
established before fire occurs.
Introduction
What is climax vegetation? It appears that we do not know in all cases
what it is.
Perhaps a case in point is the giant Sequoia (Sequoia gigantea) in Cali-
fornia. For many years Sequoia groves were carefully and stringently pro-
tected from fire. This included groves outside the National Park Service
areas. As a result, an understory of incense-cedar and white .fir thrived and
reached such heights that buildup was a threat to the giant Sequoias which
were thought to be residual of a climax forest. In effect, the cedar and white
fir appear to be climax in this area; and because of their growth beneath the
Sequoias, they are definitely protected from fire and are a serious threat to a
subclimax species, the big trees, that we wish to perpetuate.
After a number of years of study, it became apparent that the Sequoia
was dependent upon fire for its existence. Protection from fire caused such a
buildup of the climax species, cedar and fir, that a fire in Sequoia groves
could crown in the supclimax species that was to be perpetuated. Without
this understory, it would have been permissible to permit light fires to burn
through Sequoia stands. As is well known, mature S. gigantea, because of
bark thickness, can well withstand ground fire.
79
80
After many years of study and discussion, we decided to establish four or
five burning plots in Sequoia National Park and at least two burning plots in
Yosemite National Park. Before these areas could be burned, we had to
remove the buildup of fir and cedar at considerable expense. This understory
was cut and stacked in varous safe locations and, at the proper time of year,
burned. Following this, prescribed burnings of the S. gigantea areas were
initiated. Soon the regeneration of Sequoia occurred.
So, it appears that fire is a necessity in certain areas. Upon occasion, it
tak:es a number of y~ars to learn this and, perhaps, to learn it in the. most
difficult way. It certainly has taken years to overcome the idea that fire
should not be allowed in certain areas.
Perhaps you wonder why, as a representative of the National Park Service,
an agency dedicated to the preservation of all natural features, I would speak
in favor of natural fire in certain cases. Perhaps it would be well to inform
you about the reason for the establishment of National Parks.
The National Park Service was established in 1916. Its purpose is to con-
serve the scenery of natural and historic objects and wildlife within its juris-
diction and to provide for enjoyment of the same in such manner and by
such means as to leave these features unimpaired for the enjoyment of future
generations. This mandate places the controlling agency between horns of a
dilemma.
Prior to the establishment of the National Park Service, a number of areas
were set aside as National Parks, and these were administered by various
Federal and, in certain cases, State agencies. In 1916, when the Service was
established and made the controlling agency of the 16 existing National
Parks, policies were established for the management, protection, develop-
ment, and use of these areas. Since that time, policies and objectives have
evolved to a point where they are in conformance with the concepts of the
originating Act of the Service.
Presently under National Park Service jurisdiction are three different
categories of areas: recreational, historic, and natural. In these categories,
management policies differ. For example, in recreational areas the mission is
truly that of recreation. Certainly within a recreational area there are historic
and natural features that must be protected, but these are within the concept
of recreation. In historic areas, the same situation exists-the prime resources
to be protected are its historic features.
In the natural area category, the purpose is preservation of superlative
examples of our Nation's scenic beauty, wilderness, native wildlife, indige-
nous plant life, and other values of scientific significance. In this category,
we are dealing with National Parks and National Monuments.
Presidential proclamation is legally sufficient to establish a National
Monument, but an Act of Congress is required to authorize a National Park.
However, the Congress can also establish National Monuments. These areas
differ in several significant respects: National Parks generally possess two or
more unique scenic or scientific values of superlative quality, whereas Monu-
ments need only one attribute of either scientific or prehistoric value.
Administrative policies are the same for each.
The burning issue is fire. And National Park Service administrative policy
says that natural fire is a phenomenon and should be allowed to run its
course. It can be quoted:
Any fire threatening ecological resources or physical facilities of a
natural area, or any fire burning within a natural area imposing a
threat to any resource or physical facility outside the area, will be
controlled and extinguished.
The Service will cooperate in programs to control or extinguish
any fire originating on lands adjacent to a natural area possessing a
threat to natural or ecological resources or facilities of that area.
Any fire in a natural area other than one employed in the manage-
ment of vegetation and/or wildlife will be controlled and extin-
guished.
It is fairly obvious that natural fire is now being recognized as a natural
phenomenon and should be allowed to run its course. However, before fire is
allowed to run, certain areas must be delineated to ascertain whether or not
the heretofore mentioned natural or man-constructed facilities will be
endangered. It appears that, in the future, wildfires will be permitted to
burn. The allowance of fire will be predicated on ecological studies of the
areas involved. This makes necessary the study of old existing patterns of
vegetation and new ones that have evolved as a result of fire. And again, if
human life, public developments, or other agencies' lauds are endangered,
" the fire will be suppressed.
We are very fortunate that, beginning in late 1971, we will have three
additional biologists on the Alaska National Park Service staff. One of these
will be a plant ecologist, with a prime duty to make vegetative studies
relative to natural fire. Investigation by the others will greatly supplement
his work.
Our intent during the coming fiscal year is to equip our newly acquired
aircraft to make comprehensive photos of vegetation so the ecologists will be
able to evaluate the need for fire or the need for its suppression in certain
areas.
81
82
-----------------------
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska 13-14, 1971.
Effects of forest fire smoke
• • on tourism In
Mount McKinley
National Park, Alaska
Abstract
Mount McKinley National Park encompasses 3, 030 square miles of Alaska
and the highest point in North America-20,320-foot Mount McKinley.
Many tourists visiting Alaska plan trips specifically to see the scenery and
wildlife of the Park. In summer of 1969, extensive wildfires in interior
Alaska created widespread smoke palls and obscured much of the scenic
attraction of the area. During this period, visitation at the Park was higher
than in previous years, but length of stay per visit was lower. Smoke condi-
tions during this season apparently did not greatly affect tourism in Mount
McKinley National Park.
For my part of the National Park Service presentation today, I will make
some observations on the effects of forest fire and smoke on tourism in
Mount McKinley National Park. I'll use the term "visitor" in lieu of tourist,
however, since the latter has an unpleasant connotation for some people. We
also believe "visitor" is a more descriptive term. I'll use the 1969 fire season
as a basis, since this was the most recent year of large fires and a time with
which we had personal experience. We'll attempt to analyze why people
come to the Park, what they do when they're there, what we would expect
the effects of smoke to be upon these use patterns, and finally, what actually
did occur when we had this smoke and fire problem.
The Park is located less than 90 airline miles south of Fairbanks and is
3,030 square miles of alpine tundra, spruce forest, mountains, and glacial
streams. There is a potential for large fires, and because the staff is small, we
must rely upon the Bureau of Land Management to handle our major fire
control activities. This cooperative agreement has been beneficial for us, and
we are pleased with the Bureau's assistance and capabilities.
A look at some of the reasons people visit the Park might give us some
insight into what will happen when there is heavy smoke in the area. A
recent report by the Federal Field Committee for Development Planning in
Alaska, especially the chapter entitled ·"Alaska Recreation and Tourism
Resources," listed what their research had shown to be the primary reasons
----------------------------
Ivan D. Miller
National Park Service
U.S. Department
of the Interior
McKinley Park,
Alaska
83
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visitors come to Alaska.
They found that approximately 80 percent of people came to see the
scenery and wildlife, and many of these came specifically to see Mount
McKinley. Not all of this latter group visited the Park, since the mountain
can be seen from many places within the State, and a special visit to the Park
is not necessary to fulfill this objective.
Generally, we could say that about a fourth of Alaska visitors make
Mount McKinley National Park a prime goal in their visit to the State. Why
do they come to the Park? There are several reasons.
The mountain itself, the highest in North America (20,320 feet), is a
major attraction. The unparalleled scenery people expect in Alaska is found,
in part, within this National Park. Wildlife is certain to be here too; and since
animals are protected, you can almost be assured of sighting some as you
travel along the main road in the Park. Finally, since this is a National Park,
it has an intrinsic value of its own. People travel from many parts of the
world to see another National Park; it has a special undefinable meaning and
value for them.
How do people visit the Park? Until now, the majority have come by train
from either Anchorage or Fairbanks, stayed at the McKinley Park Hotel, and
taken the concessioner's bus tour through the Park. Many arrive by private
vehicle over the Denali Highway, and we expect many more vehicles when
the new Anchorage-Fairbanks Road is completed. Most of those in their own
cars camp within the Park, and we have fairly extensive campgrounds. Some
people fly to the Park. Many land, but most are satisfied simply to view the
scenery in passing.
What would we expect to happen during a summer season when there is
much fire activity? The obvious thing, of course, would be a decrease in total
visitation. If heavy smoke lessens visibility, you would expect fewer people
to even attempt viewing scenery. You might expect a decrease in the
length of stay by those people who did arrive. Similarly, I would predict that
individual activities would be restricted mainly because of the smoke irritant
factor, wildlife restlessness, poor photographic possibilities, etc. Some have
suggested that we could expect more visitor complaints and less camping,
both in auto campgrounds and in back-country camping. Quite likely, there
would be fewer people participating in the bus tours. We would expect a
reduction in mountain climbing. Mount McKinley and nearby peaks have
popular routes, and a thick layer of smoke around the mountains would
probably decrease this sport.
During the summer of 1969, the Park was affected, as was much of
Alaska, by extensive fire activity. The interior was very dry, during June
especially, and we prohibited all campfires. The Park had several large fires,
and a heavy smoke pall covered the terrain, obscuring even the mountain
peaks from on-the-ground viewers. This gave us a chance to check our
hypotheses, even if we could not use precise investigative techniques and had
------------·-·
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to resort to empirical knowledge and hindsight.
First of all, we checked the visitation records for any changes. We asked
for observations from residents that had been in the area for some time to
see if their observations were close to ours. We consulted the ranger station
logs and checked visitor comments in registration books. And finally we
tried to recall personal observations and thoughts from the summer.
What did happen? Much to our surprise, visitation did not decrease but
increased considerably. It was up several thousand over previous years and
was greater than the following year (I think we cart assume that the Clecrease
in 1970 was a result of the economic slowdown experienced throughout the
country).
I had made an interesting note in the Wonder Lake Ranger Station journal
near the end of June 1969, "Mount McKinley has not been visible for 21
straight days." Apparently the word did not get out; or if it did, no one
cared, because people came anyway. As suspected, though, there was a
decrease in the length of stay by individual visitors. More people arrived, but
they left sooner than they normally would.
Individual activities also increased. Back-country use was up, probably
because of lack of rain. Photographers became even more zealous to capture
the scenes and wildlife on film.
Instead of visitors' complaining about the smoke and heat (and blaming
the Government-an easy target), the majority of people expressed concern
for the land and fauna and appreciation of the suppression efforts.
Mountain climbing also increased. A reviewing of the expedition reports at
the end of the season showed that although there was much smoke at lower
elevations, the weather was better than normal at higher points. Once the
climbers got above the smoke, they experienced generally good weather.
These results were very unexpected. Although we are not certain of the
reason or combination of reasons, the most acceptable explanation seems
related to long-range planning. It costs a great deal to come to Alaska, and
visitors from other States especially must plan and commit funds long before
their trip. Reservations must be made far in advance for tours, and those
driving are usually committed to time and goals. It may also be that with the
great distance involved, prospective visitors are not aware of conditions they
will encounter in the State.
In summary then, I think we can say that Mount McKinley National Park
is a major visitor attraction, and heavy smoke or fire will not affect the
amount of Park travel but may decrease visitors' lengths of stay. The quality
of the experience of visiting this area may also be lessened. Perhaps someday
social scientists will be able to help us measure this loss.
These are personal observations and not principles we should apply to all
National Parks. The points may not even be valid for Mount McKinley
National Park the next time there is a Statewide fire problem.
85
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86
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Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Fire effects and
rehabilitation methods-
Swanson-Russian
Rivers fires
Abstract
During summer 196 9, fires burned 86,000 acres of the Kenai National
Moose Range, south-central Alaska; two fires accounted for 99 percent of
the burned area. Suppression efforts involved nearly 5, 000 men; 135 miles of
catline were constructed, and 822,000 gallons of retardant used. Funds allo-
cated for burn rehabilitation totaled $900,000 for FY 19 70 and 19 71.
Effects of the fire on wildlife were apparently light. There were nocon-
firmations of dead or burned bear, moose, or caribou; although small
mammals probably suffered, I year later voles, shrews, and grouse were
reinhabiting the burned area (possibly in reduced numbers). There were
indications of heavy salmon mortality immediately after the fires, but actual
cause was not determined. No long-term effects on fisheries were noted.
Rehabilitation efforts include seeding and fertilizing over 13,000 acres,
and using LeTourneau "tree-crushers" to knock down fire-killed trees on
30,000 acres. These efforts appear to be very successful in reducing fire
danger from standing snags, aiding animal access to browse species, and
improving the overall appearance of the landscape.
Introduction
Wildfires burned approximately 86,000 acres of forested land on the
Kenai National Moose Range during 1969. Of the total land area affected, 99
percent was burned in two fires, the Russian River and Swanson River fires
(fig. 1 ).
The Russian River fire began June 14 in the Chugach National Forest, was
contained by the morning of June 15, and was in the process of being
mopped up in the afternoon when rapidly rising east winds (from 10-40
knots) reactivated the fire which jumped across the Russian River ravine
(approximately one-eighth of a mile wide) onto Moose Range lands. For 5
days, pushed by high afternoon winds, the fire burned 6 miles westward,
jumping the Kenai River and up Shelakh Mountain, where it was controlled
June 20 after velocities of wind lessened. It had burned 2,600 acres-2,300
John B. Hakala,
Robert K. Seemel,
Robert A. Richey,
and John E. Kurtz
Bureau of Sport
Fisheries and Wildlife
Fish and
Wildlife Service
U.S. Department
of the Interior
c_
I
87
88
of which occurred on Moose Range lands. Mopup continued until June 25
when infrared scanning aircraft reported the fire out.
The U.S. Forest Service was in charge of the fire. They estimated suppres-
sion costs at between $800,000 and $1 million.
The suppression involved 918 men, 22 pumpers, 13 dozer tractors, and
three air tankers. Twenty miles of "catline" were constructed, and 91,000
gallons of fire retardant were dropped.
...
30'
...
UNITED STilTES
DEPARTMENT OF THE INTERIOR
COMPILED IN THE DIVISION OF ENGINtERING
FROM SURVEYS BY u.S.G.S 6 B S.F 6 W.
KENAI NATIONAL MOOSE RANGE
ALASKA
151°00' "''
SEWARD MERIDIAN
PORTLANo,.oREGON Scale ;,' -....: .... ~.;,~..,;:;~....;:::...~~ .... ~
Figure I.-Swanson-Russian Rivers fire areas.
--------~-------·--------
FISH AND WILDLIFE SERVICE
BUREAU OF SPORT FISHERIES AND WILDLIFE
150"00'
·~· """ i ~ DECLINATION
~I IR ALASKA 362 408
The Swanson River fire began on August 3 and was contained and in the
process of mopup on August 4 , when again, high winds from the southwest
with velocities of 20-25 knots reactivated the fire causing it to crown and
sprea d 5 miles to the northeast. In subsequent days, a similar pattern fol-
lowed, with high, gusty winds up to 40 knots changing the direction of the
fire and pushing it on new courses with runs of 11 to 14 miles until ca lming
winds allowed it to be brought under control on Augusl 28 .
The fire burned 86,000 acres -83,000 of which occurred on Moose Range
lands. Mopup continued until October 8 when the last fire crew left.
"Smokes" continued to be sighted throughout the 1969-70 winter , but the
fire was finally declared out in May after spring breakup and after the area
had been flown over by infrared scanning aircraft. Numerous "smokes" were
reported during the following summer, all of which were checked out but
proved to be erroneous. Apparently , accumulated carbon dust from fire-
killed spruce had been dislodged by wind action and was reported as fires.
The Bureau of Land Management, through a cooperative agreement, has
primary responsibility for fires on the Kenai National Moose Range and
fought the fire to the "bitter end." At the h eight of the fire, 30 helicopters ,
79 pumpers , 100 dozer tractors , and over 4 ,000 men fought the fire. With
731 ,000 gallons of fire retardant dropped, suppression costs varied from $8
million to $21 million , depending on who was doing the estimating and for
what purpose.
Figure 2.-"Cat" constructed firebreaks.
89
9 0
Both fires were caused by careless campers. Though they were investigated
thoroughly , no cases were made .
Mother Nature was attempting to tell us something-in critical areas, hit a
fire with everything you've got before she becomes angry and takes over.
Weather and wind conditions, in both cases , dictated the behavior of the
fires.
Due to the high recreational, wildlife, and esthetic values of the land
burned, while the fires were still in progress , it was determined to begin
immediate restorative work with the cost of the initial phases added directly
to the cost of the fires. This work consisted of rehabilitating firebreaks (fig.
2) constructed in suppression efforts by respreading berms and dozed trees
over exposed mineral soil, constructing water bars, terracing slopes exceeding
10 percent, and fertilizing and seeding critical areas to an annual rye grass
(Lolium multiflorum).
There were 115 miles of "dozer" constructed fireline reworked, totaling
1,000 acres in the Swanson River burn (fig. 3). The project was accom-
plished in 25 days under the direct supervision of the Bureau of La n d
Management at a cost of $400,000. An excellent rehabilitation job was
accomplished.
As a result of the unusu al publicity associated with the fires, Congress
appropriated supplemental funds in February 1970 for additional rehab ilita-
Figure 3 .-Reworked catlines totaled 115 miles.
tion work. Accordingly, the Kenai National Moose Range received $680,000
for the balance of fiscal year I 970 and $220 ,000 for fiscal year 1971.
Projects which have been completed include 13 ,449 acres fertilized with
33-1/3 percent ammonium nitrate and seeded to an annual rye grass to
prevent sheet and gully erosion on slopes over 10 percent (fig. 4). Fertilizer
was applied at the rate of I 00 pounds per acre and seed at 10 pounds per
acre; roads were repaired and regraveled along with parking areas and camp-
grounds destroyed or severely damaged during fire suppression activities.
Boat ramps , toilets , fire grates, tables , and log barriers were replaced wher-
ever needed. Three LeTourneau tree crushers were purchased to knock down
and crush fire-killed trees in critical areas , eliminating them as a future fire
hazard and creating a buffer zone between the settled and heavily indus-
trialized area to the south and west of the Moose Range (fig. 5), as well as
providing favorable wildlife habitat.
These machines are diesel-electric with individual electric motors powering
each of three large shearing drums. Each crusher had "bugs" to be "ironed
out." but, despite late arrival of the machines, major breakdowns , and a
possible occupational health hazard (which shut down the project for 1
month during evaluation), 1 0,000 acres of fire-killed trees have been worked.
An additional 20,000 acres is programed to be worked.
Figure 4.-A total of 13,449 acres were aerially fertilized and seeded to an annual rye
grass.
91
9 2
Figure 5.-Three LeTourneau tree crushers were purchased to knock down and crush
fire -killed trees .
Impact of Fire on Vegetation~
Wildlife~ and Recreation
VEGETATION
The Swanson River fire burned in stands of every major type of vegetation
represented in the Kenai lowlands. These include black spruce and white
spruce, birch, aspen , their mixtures , and the various bog types.
The dense spruce stands provided excellent fuel and carr~ed the fire when
the wind reached 15-20 knots. When the fire was running as in the evening of
Aug u st 7, an area 1 V2 miles long ignited at one time. Burned needles and
leaves were carried over 50 miles beyond the fire by the strong winds.
When the fire was carried through spruce stands , it killed all the above-
ground portions of plants. Some large areas within these stands were burned
to mineral soil.
The black spruce retains its cones and has a plentiful supply of seed to
spread following fire. No doubt this has occurred in the Swanson River fire
as it did in the 1947 burn .
In hardwood stands of birch and aspen, the fire burned into the thick
dry duff around the bases of the trees. In many cases, the fire consumed
enough of the shallow root system to allow the trees to be easily uprooted
by the wind. In other cases, the trees were killed or weakened but re-
mained standing.
The birch trees in this area tend to have seed crops every year. The trees
had a good crop in the fall after the fire. The seeds from birch are distributed
at intervals throughout the winter and can be observed in large numbers
following winter rains. No doubt, snow conditions (such as crust) and wind
velocities are largely responsible for distances seeds are distributed. Probably
portions of the bum area will come back into dense stands of birch as have
areas in the 194 7 bum.
The tree crushers are laying low the fire-killed stands, primarily black
spruce. These stands are of pole-size trees and have no significant salvage
market. Some are being used locally for fence poles and posts. We feel that
the tree crushers are doing a satisfactory job. The diesel-electric system of
power is new to all of us. The time lost due to breakdowns has been signifi-
cant but apparently not a result of our inexperience or lack of training.
After the crushers make one pass over an area, most of the material is on
or near the ground. All of the fire-killed trees do not fall forward in front of
the machines as living trees would. For this reason, the crushing is not as
uniform as if the machines were working in green stands. If a third pass is
made over an area by the crushers, all of the big material is either on or
below the ground surface. Most of these stands tend to be on fairly level
ground.
When hills or ridges are too steep for efficient operation, those particular
portions of the stands are left to "break up" the monotype left by the
machines. Also, most of the live hardwood trees in these stands are left for
seed source and esthetics.
In contrast to a black and brown junglelike mat of sticks left from the 1947
bum, the area run over by the LeTourneau tree crushers is very pleasing to
the eye. The areas will soon look even better, and hiking in them will be a
pleasure in contrast to hiking in the 1947 bum. There is already a significant
amount of willow sprouting from decadent remnants which have been given
a new lease on life with a plentiful supply of sunshine and nutrients.
The mature stands of birch and aspen, where the burning of dry duff
destroyed the shallow roots, remain a problem. These areas (because the
trees are large with jack-strawed boles and large root wads) will slow down
the tree crushing operation but hopefully will reseed to birch.
The fire consumed the grasses and sedges along Swanson River and other
streams. These areas looked extremely bad from an environmental stand-
point at the time, but the bases and roots of the plants had not been
destroyed, and the grasses and sedges were starting to "green up" again
before the fire was demanned.
L
93
94
The windfallen trees in Swanson River were an important environmental
problem. As the fire was demanned, the Bureau of Land Management sent
crews in canoes, with helicopter support, down the river to remove these
trees. Over 580 trees were removed. The following spring (1970), a Moose
Range crew floated the river, removed a few additional windfalls, and cut the
remaining fire-killed trees which could have fallen into the stream.
The rehabilitation of dozed lines by spreading the berm piles back over
the line is of tremendous value. The material provides a more natural seed-
b~<i anci, i1ll11QSt Cl}s~s, C011Ja.insQrQp(lgule1). It physi~ally prevent~_er()siQ!l
and obstructs off-the-road vehicle use which would otherwise increase the
problem of erosion.
The summer after the fire, there was a good crop of fireweed in most of
the burned black spruce stands. Dense stands of horsetail were also common.
The greatest crop, however, was the morel mushroom. Both people and
moose consumed them in vast numbers.
WILDLIFE
Concern for the welfare of wildlife during and after the August 1969
Swanson River fire was important to many fire personnel and local residents
as well as the refuge staff. Numerous inquiries about the status of the resi-
dent moose population and other wildlife directly affected by this fire were
common.
A wildlife observation report form was distributed to pilots and crew
leaders, and several were posted at central dispatch locations. These forms
requested details of any wildlife observed in and near the fire area. A special
request for knowledge concerning dead wildlife was included, but the
response was nil. Not only did most report forms remain blank, but personal
contacts with the firefighters, line bosses, and helicopter pilots generally
resulted with negative responses. A few comments indicating losses of moose
or black bear at several isolated locations were investigated without positive
results. One crew leader indicated he had observed the fire-singed side of a
black bear and of one moose. During an aerial survey, only one moose
skeleton was observed, to my knowledge, immediately south of the Swanson
River, near the fire origin. This animal may or may not have been a fire
casualty.
On August 12, a noticeable number of dead fish were observed along the
lower 8 or 10 miles of the Swanson River. Earlier reports of the arrival of
salmon proceeding upstream indicated many fish were jumping wildly in and
out of the water and thrashing savagely about. Soon after passage of the fire
front and when the fire boss approved canoe travel, a river survey was
conducted by Alaska Department of Fish and Game Fishery biologists.
Although 501 dead adult salmon were counted, the kill probably exceeded
700 adults. Dead juvenile salmon and rainbow trout were too numerous to
count. Water samples were collected during the survey to help determine the
cause of the die-off but were without positive clues although the samples
--------------~-------------~----------~--------
indicated high carbonate levels.
Nearly 235,000 gallons of Phoschek fire retardant had been air dropped
by August 11 ; another 46,000 gallons followed the next day, much of it
deposited near the Swanson River and its tributaries.
Despite the severity of the salmon die-off, a large escapement was realized.
Ocean-fresh salmon moved into the Swanson River within 4 days after the
die-off was first recorded. On August 24, more than 300 salmon were
observed 2 miles upstream. Apparently, whatever had been killing the fish
-was no ronger--present-afatoxiclevel. SuosequenTsurveys inaicateoonly tf1e
early arriving silver salmon were affected.
Some aerial observations of wildlife movements and activities were recorded.
At no time were moose observed, either singly or in groups, moving hur-
riedly out of the path of the approaching fire. The fire area actually con-
tained a relatively small moose population. Hours and even days of smoke
and associated firefighting activities had probably resulted in substantial
wildlife movements from the area prior to any immediate danger.
During one spectacular fire run to the north, we observed the fire front
traveling 2.5 to 3 miles per hour; light debris was blown one-half to three-
fourths of a mile ahead of this front, and it quickly ignited the dry grass and
other fuels in which it feii. Several passes were flown along the extended
flanks of the fire without sighting harried wildlife.
·• At one small lake (one-eighth of a mile wide), a swan family with two
cygnets was sighted in the water and a moose was feeding near the shoreline
while the spruce trees torched along the opposite shoreline and went up in
flames.
A swan pair with three cygnets was observed several days on Cow Lake in
heavy smoke during periods of active fire around the lake. This family
moved from one end of the lake to the other away from the burn but did
not leave the lake although all birds had fledged.
One black bear with three cubs was sighted near Doroshin Lake sur-
rounded by fire on three sides and moving eastward across an open muskeg
away from the fire. She was highly excited, but we were unable to determine
whether the fire and smoke or two passes of the aircraft had contributed to
her actions.
A small group of nine to 18 caribou have resided 2 miles north of the
Kenai Municipal airport for several years. At one point, when the fire had
reached south along Beaver Creek and west to an aircraft radio navigational
facility, a group of caribou was observed lying in the open, low vegetation of
that area completely surrounded by the burning fire. Later that day, the
animals were again moving westward without apparent harm.
Undoubtedly, the fire took its toll of the smaller animals. Red squirrel,
snowshoe hare, voles, shrews, and some birds (small bird skulls were found
along the Swanson River) were directly affected.
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A study of small mammals conducted by Larry Ellison 1 near Finger Lakes
revealed some enlightening information. Immediately after the fire, dead
voles were found in the smoldering ashes. But a year after the fire, numbers
of voles seemed to be nearly equal inside and outside the burn, although
numbers of shrews may have been fewer in parts of the burn. The insecti-
vorous diet of shrews might make them more susceptible to habitat dis-
turbances by fire.
Mr. Ellison believed traps set deeper inside the perimeter of a burned area
might have shown a more significant effect of fire on voles. However, the fire
left many islands of unburned habitat throughout the burn. Apparently,
dozing of fire lanes (up to 50 yards wide) disturbed the habitat of small
mammals more than did the fire. Dozing uprooted trees, removed much of
the organic matter, and left few hiding places for small mammals. The fire, in
contrast, left much cover in the form of tangles of roots of standing trees
and charred organic matter.
Continuing a 5-year study of spruce grouse at Finger Lakes, Mr. Ellison 2
noted on one 4-square-mile plot, only 18 broods were in the burned fraction
in 1970, compared with 41 on the same area in 1969. Apparently, the fire
had reduced the carrying capacity for grouse broods by 56 percent.
Frequently, broods were found in sites totally burned, i.e., in ashes. No
food was available, so the birds were apparently just moving through such
areas, which represented a very small portion of the burn (less than 1 0
percent). Regrowth of vegetation has been rapid over most of the burn. One
reliable report was received of a hen nesting 200 yards inside the burn in
ashes under a charred log.
During July, 1 0 adult and five yearling hens were identified inside the
burn, and 11 adults and 12 juveniles outside. Data of movement of four hens
with broods which were sighted three to eight times each during the past
year also suggested adult hens returned to the burn after being forced out by
the fire. Movement of a fifth adult hen suggested the opposite-that after the
fire forced her out of former home range, she moved into unburned habitat
to raise her brood.
Nests of the trumpeter swan at Mink Creek Lake and Beaver Lake were re-
established during the spring of 1970. Although their surroundings remained
fire scarred, seven cygnets hatched at Mink Creek Lake and one at Beaver
Lake.
Today, tracks and sightings indicate few moose within the burn. Some
have passed directly through, a few remain near the browse source at Beaver
Lake, and some animals are within the Swanson River oilfield area.
1 L. N. Ellison. Small mammal study in Swanson River burn, Kenai National Moose Range.
(Unpublished report on file at Kenai National Moose Range.)
2 L. N. Ellison. Spruce grouse reproduction for 1970 and over-winter survival for 1969-70, Kenai
National Moose Range. (Unpublished report on file at Kenai National Moose Range.)
r
RECREATION
There were two main recreational losses-direct loss in visitor use due to
closures and a long-term (20-year) loss in recreational land values.
The direct loss is figured according to the value of $21 per visitor day, as
calculated by Dr. Steinhoff. 3
The long term is prorated over a 20-year period, assuming a normal
4-percent appreciation in land values. The land value lost over the next 20
years amounts to $424 per acre. These figures are also extrapolated from Dr.
Steinhoff's report.
I. Visitor use loss
1. Russian River fire
Closed to public use, 6114-713169
Estimated 50,000 visits lost
2.5 visits equal 1 visitor day
1 visitor day equals $21
50,000
2 _5 equals 20,000 x 21 equals
2. Swanson River fire
Closed to public use 813 -9 I 1 I 69
Estimated 80,000 visits lost
2.5 visits equal 1 visitor day
1 visitor day equals $21
80,000 equals 32,000 x 21 equals 2.5
Subtotal
$420,000
$672,000
$1,092,000
II. Recreational value lost
Recreational value of Moose Range land equals $39 per acre
20 years to restore
80-percent loss equals $31.20 per acre
1. Swanson River fire
$31.20 x 13.59 equals $424 per acre
424 x 73,865 equals
2. Russian River fire
$31.20 x 13.59 equals $424 per acre
424 x 2,300 equals
Subtotal
Total recreational loss
$31,318,760
$975,200
$32,293,960
$33,385,960
3 H. W. Steinhoff Values of wildlife and related recreation on the Kenai National Moose Range.
(Unpublished report on file at Kenai National Moose Range.)
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There probably is a short-term reduction in visitor use due to the publicity
these fires received. In other words, some people will probably avoid these
areas if they know they are burned. On the other hand, some people may be
attracted to the area to see the results of a forest fire. The numbers will
probably balance out, although the length of stay may be reduced in the fire
areas for a few years.
The only constructed recreational facilities that actually burned were
Sunken Island Lake, Mosquito Lake trail, Forest Lake trail, and part of
Surprise Creek trail. These areas normally do not receive heavy public use.
Beaver, Finger, and Elephant Lakes, with high recreational potential, were
severely damaged during the fire.
At Kenai-Russian River and several waysides, the burn can be seen from
the camping areas, but the camping areas are not affected. The esthetic value
is reduced, but this probably has little effect on public use.
According to Dr. Steinhoff, the visitors valued the Russian River area the
highest of all Moose Range lands. Th~ users indicated this area should be
allocated 30.7 percent of the total management effort. The Swanson Riv~r
area was valued at 16.7 percent of the total. The refuge users placed these
two areas at 47.4 percent of the total value of the Moose Range for recrea-
tional uses, although these areas occupy less than 15 percent of the total
land area.
One of the reasons the people place such a high value on the Russian River
arell is the salmon fishery. Each year, thousands of people (average 15,000
fisherman days) crowd into a l-mile stretch of the Kenai-Russian rivers. An
average of 10,000 salmon are taken annually.
There is reason for concern when considering only the salmon resources.
Since this area is mountainous, has a loess soil, and is susceptible to erosion,
there was a possibility of siltation of the salmon streams. For this reason, all
dozed trails were rehabilitated, seeded, and fertilized, and the total burned
area was seeded and fertilized. To date, there has been no reduction in
salmon fishing due to the fire.
There are several recreational benefits derived from the fires, some with
immediate returns:
During the summer of 1970, the Swanson River fire area produced one of
the most lush crops of morel mushrooms ever seen in this are11. People were
attracted from far and wide to take advantage of this bonanza-2,320 people
11re estimated to have spent 6,040 hours picking mushrooms. There is a
reason to believe that mushroom picking shoulq be good for the next few
years but will gradually decrease as the vegetation grows more dense.
In the next 3 to 5 years, moose browse will have regenerated. For the next
20 years, browse should continue to improve. This will attract many hunters
and sightseers to the area as did the 194 7 bum. Over a 20-year period, we
cim expect a gain in public use that will offset the immediate loss In use
during the fire closures. · ·
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The land will become more valuable for moose, partially offsetting the
long-term recreational and esthetic loss over the next 20 years. However, it
will take much more than 20 years to bring the stands back to what they
were before the fire. Probably the recreational-esthetic loss should be pro-
rated over 100 years rather than 20 years.
Realistically, the recreational-esthetic loss can never be recovered, but
total public use will probably increase over the next 20 years due to in-
creased moose production and increased demand for public land for recrea-
tional purposes. People will be more willing to acceptless desirable land for
recreation as population pressures increase.
Literature Cited
1. Lutz, J. J. 1956. Ecological effects of forest fires in the interior of
Alaska. Dep. Agr. Tech. Bull. 1133.
2. Spencer, D. L., and J. B. Hakala. 1964. Moose and fire on the Kenai.
Third Annu. Tall Timbers Fire Ecol. Conf. Proc.
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Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Effects of fire
and fire control methods
in interior Alaska
Abstract
The taiga forest of interior Alaska lies within a broad zone of discon-
tinuous permafrost. Although the gross effects of wildfire on vegetation and
wildlife are fairly well known and understood, there is still a lack of knowl-
edge on the effects of fire on interior soils and especially in permafrost soils.
Serious erosion problems can occur in fine textured frozen soils with a high
ice content. Fireline construction with tractors in silty permafrost soils can
lead to gross gully erosion unless proper safeguards are undertaken. In some
areas, catline construction has been estimated to have caused more erosion in
the past than the actual effects of the fires.
The effects of wildfire on subarctic ecosystems are imperfectly under-
stood at best.
The intent of this paper is to explore some of the more visible gross
effects of fire and more specifically the effects on permafrost soils. I would
like to further explore the potential damages which can occur when tradi-
tional accepted techniques of fire control are applied on permafrost soils
without modification or an appreciation of what problems may arise.
Interior Alaska is defined as that area lying between the Alaska and
Brooks Ranges and from the Canadian border to the coastal tundra lowlands
on the shores of the Bering Sea. This region includes the broad flat valleys of
the Yukon and Kuskokwim Rivers and the adjacent highland areas. Perma-
frost is discontinuous throughout the area and occurs in unpredictable
patterns. Most of the lightning-and man-caused wildfires are concentrated in
this region. Climate is continental-long, cold winters and short, warm
summers.
As is to be expected, interior Alaska supports a variety of vegetative types
and associated wildlife species. A few excellent studies of the effects of
wildfire on some of the more economically important vegetative types and
wildlife species have been conducted in subarctic areas.
Palmer (3) in Alaska and Scotter (4) in Saskatchewan reported on the
effects of fire on caribou lichen range. Their findings are similar in indicating
Salvatore Deleonardis
Alaska State Office
Bureau of
Land Management
Anchorage, Alaska
101
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that lichens are slow to recover after fire, whether located in the open spruce
forest or in tundra-alpine areas. Pioneer lichen species may return in 20-50
years, and an additional 100 years or more may pass before the preferred
climax lichens again predominate.
Lutz (2) has described the gross effects of fire on most of the forest types
found in interior Alaska. Spencer and Hakala (5) have reported on the pat-
tern of forest succession after fire on the Kenai Peninsula and the effects of
this succession on moose populations.
Fire control officials speak in terms of fuel types which are in many cases
analagous to the plant associations of the biologists. Some of the more
common fuel types in interior Alaska are the hardwoods (birch, aspen,
cottonwood), the mixed hardwood-spruce, spruce, black spruce-bog,
muskeg, and alpine or tundra.
Wildlife species vary widely in their habitat requirements. Some species
may be found throughout a broad range of vegetative types, others with
narrow habitat requirements may be confined to specific vegetative types
which meet the species' needs. Changes in vegetative types, whether caused
by fire, other disturbance, or succession, will affect either the capability of
the site to support a particular wildlife species or the capability to support
the same numbers of a particular species.
Little is known, however, about the factors which influence or govern the
rate of recovery and the sequence of plant succession on a given site after
mass destruction of vegetation by wildfire under various intensities of burn.
Unknown> too, are the effects of fire on the small birds and mammals. For
example, how long does it take for small rodents to reinvade the center of a
10-acre burn? A 1,000-acre burn? A 50,000-acre burn?
Even more of a mystery is the effect of large wildfires on water quality
and soils in this region of the subarctic. Lotspeich et al. (1) reported on the
effects of fire on water quality on one fire that burned in the Tanana Hills.
Much more needs to be done, especially in a controlled situation where
water quality is monitored before as well as after a fire.
Maintenance of high water quality is essential in watersheds for domestic
and recreational use. Fire-caused siltation in anadromous fish spawning areas
could have disastrous effects. We know that in some cases siltation caused by
fire or fire control methods have affected some streams. We do not know
how long the effects last nor how soon the waters can cleanse themselves of
silt deposited on gravel beds.
Lotspeich et al. reported that the only evidence of erosion on the fire
studied was caused by catline construction and that this erosion was capable
of causing long-lasting damage to the aquatic ecosystems. Our own observa-
tions tend to confirm that most of the fire erosion problems stem from
catline construction, but we have also noted some significant soil erosion in
permafrost soils not associated with the construction of firelines. How much
of this erosion eventually enters the stream courses is unknown.
------··------·---~-~-~----~-----------------------~----------·-----·---
Our observations indicate that the most critical factors governing the
destructive effects of fire and fireline construction on soil erosion are the
presence or absence of permafrost and the degree of slope. Knowledge of the
properties of permafrost is essential to minimize mass soil wastage and
erosion even where encountered on very gentle slopes.
Permafrost may vary in thickness from a few inches to several hundreds of
feet. The upper surface of the permafrost may lie immediately below the
duff layer or several feet below the surface under the active soil layer. The
active layer undergoes seasonal thawing and freezing: Texture can vary from
coarse sand and gravel to fine silts and clays. Ice content varies widely but is
generally higher in the finer textured soils. Pure ice lenses are commonly
found in silty permafrost. Temperature may vary from just below freezing to
several degrees colder.
Temperature can be a critical factor. Permafrost at or close to the freezing
point is much less tolerant of surface disturbance. In some cases, mere com-
pression of the insulating surface vegetation can lead to melting of the ice.
Erosion has been noted on burned-over slopes underlain by silty perma-
frost. Apparently, absorption of solar heat by the fire-blackened surface was
sufficient to start melting the permafrost. The high water content after
melting created a heavy silt mud. The weight of the mud was sufficient to
overcome the forces of friction and inertia to slip over the depressed perma-
frost surface and flow downslope.
In another area, the melting of an ice lens located close to the surface
created a "blow out," the mass downward movement of a portion of a gentle
slope.
None of these areas had been disturbed in any other way except by fire.
Even more dramatic are the effects of some of our fire control methods on
soil movements in permafrost areas.
During the years 1966-70, interior Alaska was subjected to multiple large
fire occurrences. Drought conditions made control difficult if not impos-
sible. Bulldozers were used wherever and whenever available to assist in
control operations.
The objective of fireline constuction was to remove all burnable material
from the path of the fire. In permafrost areas, this involved removing the
entire insulating vegetative layer which led to very rapid melting of the
permafrost. The berms thrown to either side of the catline created effective
artificial channels. To compound the problem further, the lines were tied in
directly to the closest body of water for more effective line construction.
The conditions were ideal for an erosion problem resulting in siltation of
streams. That is exactly what happened. In some areas underlain by deep silt
permafrost soils, gullies 20-30 feet deep were created in just 2 years. In most
cases, the problems of erosion from catlines far exceeded the problems of
erosion throughout the remainder of the burned-over areas.
103
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Forbs and grasses rapidly invade undisturbed burned-over areas. Fairly
good ground coverage is usually attained within 2 years after a burn, even an
extensive burn. Areas of previously frozen silts exposed by disturbance take
much longer to develop a stabilizing ground cover. The silts are relatively
sterile and are subject to excessive drying, both of which delay recovery.
Not only did the catlines cause stream siltation, they also created rela-
tively persistent erosion problem areas for longer periods after the burn than
the remainder of the burned-over area.
No criticism is intended in describing the damages caused by tractor con-
structed firelines. None of us were capable of foreseeing the degree to which
problems would develop, and no thought was given to the actions which
could be taken to reduce or eliminate erosion from the cat trails.
Blanket condemnation of the use of bulldozers in fireline construction is
not appropriate either. In some cases, the use of bulldozers is the only
effective way to save life and property in a wildfire situation. The fire boss is
a trained expert in fighting fires, and we should not tie his hands by disallow-
ing the use of one of his most effective tools.
I am suggesting that fire bosses be trained to recognize that there are
special problems associated with the use of heavy equipment when fighting
wildfires in permafrost areas. He should be taught that there are techniques
to prevent or minimize erosion which can be used during actual construction
of the lines. There are actions which he can take when the fire is controlled
and equipment is still available on the fireline which can assist materially in
preventing erosion and hastening rehabilitation.
Above all, he should have expert backup which he can call upon to assist
him in designing measures to prevent erosion without interference to his
main job of putting the fire out. It is up to agency management to insure
that this expertise is available when needed.
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I
Literature Cited
1. Lotspeich, Frederick B., Emest W. Mueller, and Paul J. Frey. 1970.
Effects of large scale forest fires on water quality in interior Alaska. U.S.
Dep. Int., Fed. Water Pollut. Contr. Admin., 115 p., illus. Alaska Water
Lab., College.
2. Lutz, H. J. 1956. Ecological effects of forest fires in the interior of
Alaska. U.S. Dep. Agr. Tech. Bull. 1133, 121 p., illus.
3. Palmer, L. J. 1941. Caribou versus fire in interior Alaska (a study of
bumed-over lichen ranges). U.S. Dep. Int. Fish & Wildlife Serv. Progr.
Rep., 33 p.
4. Scotter, George W. 1964. Effects of forest fires on the winter range of
barren-ground caribou in northern Saskatchewan. Can. Wildlife Serv.,
Wildlife Manage. Bull. Ser.1,No.18, 111 p.,illus.
5. Spencer, David L., and John B. Hakala. 1964. Moose and fire on the
Kenai. Third Annu. Tall Timbers Fire Ecol. Conf. Proc., p. 10-33, illus.
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106
I
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Catline
rehabilitation
and restoration
Abstract
Severe erosion has resulted in the past from bulldozer-constructed firelines
in permafrost terrain. In an attempt to reduce erosion and gullying, several
water-barring techniques and seeding treatments were tested on permafrost
and nonpermafrost catlines. Standard water bars and berm dikes constructed
at 30-to 50-yard intervals on sloping terrain were effective in reducing
erosion. Vegetative check dams on permafrost soils were ineffective. Seed
growth was more successful on permafrost than on nonpermafrost soils.
Fertilized lines resulted in better seed su9.cess than unfertilized lines.
Erosion problems resulting from use of cats on fires has generated rehabili-
tation studies designed to provide information useful in catline restoration
projects. Several types of water-barring techniques and seeding treatments
have been tested. The following water-barring methods were evaluated for
effectiveness:
Standard Water Bar-Permafrost Soil
Water-bar construction using solid and organic material at approximately
50-yard intervals on sloping terrain was effective on permafrost soils. Water
was diverted into undisturbed vegetation adjacent to catlines. This work
should be completed immediately after a fire prior to severe permafrost
melt, which co'mmences almost immediately after vegetative mat removal
(fig. 1 ).
Standard Water Bar-Nonpermafrost Soil
Water bars on nonpermafrost soils were effective in decreasing erosion
damages. Water bars are necessary in these soils when any degree of slope is
present. Erosion is usually not as rapid and dramatic the first ~eason or two
as on permafrost areas. Past ob~ervations, however, have pointed out that
severe erosion on nonpermafrost soils can occur when left untreated. Prefera-
Roger Bolstad
Bureau of
Land Management
Fairbanks District
and Land Office
107
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bly, water-bar construction should take place immediately after the fire.
However, delay in construction is not as critical as on permafrost soils, and
barring could be done a few weeks after the burn without severe effects
provided heavy rainfalls do not occur.
Berm Dikes or Dams-Permafrost Soil
Construction of berm dikes at 35-to 1 00-yard intervals along approxi-
mately 10 miles of catlines was accomplished on Fire OE7 adjacent to the
Taylor Highway. Diking was done in October 1968 after the ground had
frozen and cats could work without getting stuck.
Berm dikes were effective in minimizing erosion. Ponding of water was
common above many of these dikes. This type of construction should be
completed immediately after the fire is out. Leaving this type of work until
late fall can generate problems (cold temperatures, deep snows, closed roads,
unfrozen soil pockets, deep erosion channels, etc.).
Vegetative Check Dams-Permafrost Soil
Check dams constructed from logs and branches on ALPHA trails near
Fairbanks were completed by the military in the summer of 1969. These
dams, located at approximately 1 00-yard intervals, were an ineffective
erosion technique on permafrost soils. Ice melt underneath these dams
created severe erosion channels. Deep deposits of mud were observed on the
Figure I.-Effective water bar. Photo taken in June.
I
Elliott Highway, and State Highway Department personnel used graders to
remove these deposits. The problem became so troublesome that cats were
required to construct berm dikes at close spacing along this trail. Results
were effective and erosion was nearly stopped. Although use of vegetative
check dams on permafrost soils is ineffective, their use on nonpermafrost
soils can effectively deter erosion.
Example of this can be observed along the Livingood to Yukon River haul
road.
In addition to water-barring tests, the following trial seeding projec;t has
been designed to provide rehabilitation information:
King Creek Fire Rehabilitation Project
Experimental rehabilitation treatments involving applications of seed and
fertilizer on King Creek Fire catlines were started in the fall of 1969. The
work involved a variety of seeding treatments to test fall and spring applica-
tion on permafrost and non permafrost soils. Portions of lines seeded in fall
and spring were fertilized to test response of seed to fertilization. The
following treatments were completed:
FALL TREATMENT
Approximately 2 miles of catlines, involving I mile of permafrost and I
mile of nonpermafrost soils, were seeded by cyclone hand seeders on October
4, 1969. The following grass mixture was applied:
200 pounds Manchar smooth brome
I 00 pounds Kentucky blue grass
300 pounds mixture applied at 40 pounds per acre
No snow was on the ground during application. October was selected as an
ideal seeding time since cold temperatures persisted which eliminated any
possibility of seed germination resulting in frost kill of seedlings.
SPRING TREATMENT
Two miles of catlines involving I mile of permafrost and I mile of non-
permafrost soils were seeded onto snow surfaces by helicopter on April 20,
1970. The following grass mixture was applied:
60 pounds Reed canary grass
60 pounds timothy
60 pounds sweet clover mix (white and yellow)
60 pounds rye
60 pounds Manchar smooth brome
20 pounds Kentucky blue grass
320 pounds mixture applied at 40 pounds per acre
Snow depth averaged 12-18 inches which upon melting provided moisture
for the seed and water rivulets to aid in covering the seed with soil.
109
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A fertilizer application of 300 pounds per acre was applied by helicopter
on April 20, 1970, onto fall and spring seeded lines. A 20-20-10 pellet-fo r m
fertilizer was used as recommended after soil analysis by the University of
Alaska Extension Service .
Field observations were made in June and in August 1970 to measure
seeding success after one growing season. The following information was
gathered from trial seeding plots:
F igu re 2 .-Permafrost area-fall seeded, fertilized . Photo taken in June at start of
germination.
Permafrost plot-fall seeded, fertilized.-Germination of seed was well
underway by June. Water-saturated soil was common due to melting and
runoff of surface ice. Permafrost depths were generally less than 2 feet below
the soil surface and prevented good drainage. Downhill water movement
formed erosion channels in June.
Observations in August indicated good response of Manchar smooth
brome on this plot. Surface water movement had decreased by August and
soil was stabilizing. Kentucky blue grass response was poor. Top growth of
Figure 3.-Pennafrost area-fall seeded, fertilized. Photo taken in August showing seed
response.
111
112
brome was less than 8 inches. No evidence of flowering was observed among
seeded species (figs. 2 and 3).
Permafrost plot-fall seeded, no fertilizer.-Seed response was fair, but
heights and densities of plants were not as good as on the fertilized perma-
frost plot. Manchar smooth brome was the dominant grass species observed.
Soils were spongy and wet in June with drying evident by mid-August.
Permafrost was less than 2 feet below the soil surface.
Figure 4.-Nonpermafrost area-fall seeded, fertilized. Photo taken in August of seed
response.
Permafrost plot-no treatment-Natural revegetation had started with
some evidence of sedges, grasses (Calamagrostis, Eriophorum, Equisetum),
and small mosses. Plants were small and not in sufficient abundance to
effectively deter erosion . Water-saturated soils persisted on this site, and
downhill movement of water occurred in mid-August.
Nonpermafrost plot-fall seeded, fertilized.-Well-drained soils with minor
erosion problems were observed on this plot. Seed response (Manchar
Figure 5.-Control area-nonpermafrost location. Photo taken in August.
113
114
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smooth brome) was evident mainly in cat track depressions where moisture
retention and seed coverage occurred. Ungerminated seeds were common on
soil surfaces between track depressions. Dominant seeded species growing
was brome grass. Lack of moisture and soil coverage of seed appear to be
limiting factors prohibiting good plant growth on this plot (fig. 4 ).
Nonpermafrost plot-fall seeded, no fertilizer.-Grass growth (brome) was
fair but spotty on this study area. Plant growth occurred mainly in cater-
pillar track depressions. Overall success of seeding was not as effective on
this plot as on fertilized areas. Soils were well drained with little evidence of
erosion.
Nonpermafrost plot-no treatment.-Little or no natural revegetation was
observed at two of the three established photo points. Growth of Equisetum
was evident on the third control site where soil moisture capacity was
greater. Overall examination of untreated nonpermafrost catlines indicated
poor natural revegetative recovery (fig. 5).
Permafrost plot-spring seeded, fertilized.-Seed germination was good,
but plant sizes were smaller on lines seeded in spring than those seeded in
fall. Individual grass species were difficult to identify on spring seeded cat-
lines due to immaturity of plants. Examination of the entire plot indicated
plant densities to be greater from seed applied in fall than from seed applied
in spring.
Permafrost plot-spring seeded, no fertilizer.-Size and density of plants
were poorer on this unfertilized plot than on fertilized permafrost lines. Wet
spongy soils persisted through mid-August on this study area with some
erosion taking place.
Nonpermafrost plot-spring seeded, fertilized.-Examination of this plot
\indicated poor seeding success compared with the fall seeded nonpermafrost
line. Brome was the dominant seeded species present. Again, grass grew best
in cat track depressions.
Nonpermafrost plot-spring seeded, no fertilizer.-Growth of plants was
poor on this plot compared with growth on fertilized lines. Few erosion
problems were evident due to well-drained and level terrain.
General Comments
Several growing seasons will be required to adequately evaluate effective-
ness of various treatments in erosion damage control. Preliminary observa-
tions after one growing season did indicate better seed response from fall-
than from spring-seeded lines on permafrost and nonpermafrost soils. Hand-
seeded lines during fall application may have resulted in somewhat heavier
seed application than from aerial treatment. Rotor wash and side winds may
have resulted in some seed landing adjacent to catlines. However, seed
distribution on snow surfaces during spring seeding indicated good seed dis -
tribution where ex amined . Brome appeared to grow best of all species
seeded.
Brome seeding rates were higher in the fall than in the spring application
which also may have contributed to the rather light response from spring
seeding.
Figure 6.-Erosion stabilization by seeding-permafrost area. Photo taken in August.
115
116
Seed growth was more successful on permafrost than on nonpermafrost
soils (fig. 6). Lack of soil coverage of seed and absence of moisture appear to
be among limiting factors on nonpermafrost soils. Drilling rather than aerial
application of seed on nonpermafrost soils may result in better seeding
success. Aerial or hand broadcast seeding methods would be effective for
seeding permafrost soils. Fertilized lines resulted in better seeding success
than unfertilized lines.
Water bars and/or berm dikes at 30-to 50-yard intervals on sloping terrain
in combination with seed and fertilizer would be effective techniques in
decreasing catlin·e·erosion damage.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
A short history of the
fire weather service and the
''Federal Plan for a National
Fire Weather Service"
Abstract
A short history of the fire weather service is presented with a report on
progress made under the "Federal Plan for a National Fire Weather Service. "
The highlights of the plan and its application to the requirements of forest
and range management interests in Alaska are stressed. The services now
provided are contrasted with those services that are possible under the pre-
sent level of meteorological development.
The fire weather service is one of the National Weather Service's oldest
programs. As with many government services, it has had its periods of
growth and stagnation, all closely related to periods of economic growth and
recession and national emergencies. Currently we are maintaining the pro-
gram at the level reached in fiscal year 1968.
The first record we have of any special forecast service to forestry inter-
ests was in 1913. At that time, what is now the National Weather Service was
asked to provide warnings of east winds in the Columbia River Gorge. These
are strong, very dry winds. The following y~ar, wind warnings were issued
during the fire season for Washington, Oregon, Idaho, and Colorado.
Beginning in 1916, all district forecast centers were authorized to issue
fire weather warnings. In 1924, the first meteorologists were assigned to
provide the service, one at Seattle, Washington, and one at Portland, Oregon.
In 1926, a red-letter year, the first funds were provided by Congress for the
fire weather service.
In 1929, the U.S. Forest Service and the California State Division of
Forestry furnished a truck equipped with a radio receiver and weather instru-
ments for use as a forecast office at large fires. The radio receiver was used to
copy weather observations transmitted by Morse code from the Navy radio
facility near San Frane<isco. This was the forerunner of .the mobile fire
weather units we use today. In 1937, funds became available to provide four
panel delivery trucks for conversion to mobile units.
~~~~~~~--~--~~----
Harry L. Swift
National Fire
Weather Coordinator
National Oceanic and
Atmospheric Administration
National Weather Service
Silver Spring, Maryland
117
118
During World War II, the service was provided as best possible considering
the manpower shortage and the heavy demands on the National Weather
Service by the military and related agencies. Following the war, the fire
weather service stagnated and even deteriorated to some extent.
By 1950, the requirement for fire weather forecasting had become acute
with at least one large private association urging Congress to provide funds
for expansion of the service. None were received.
During this period, some States provided aid under cooperative agree-
ments to establish or strengthen the fire weather service at five offices.
In 1959, National Weather Service officials began working with forest and
range management agencies to draw a plan for funding and providing fire
weather service to all fire protection and related agencies. Our present
"Federal Plan for a National Fire Weather Service" is a revision of the
original plan drawn by this group.
Originally, the plan had three phases or steps, to be completed in 3
years. However, it became apparent that funds would not be made available
to implement the plan in such a short period. The plan was changed, and the
three phases covering the field service program were broken into seven smal-
ler steps. Four-and-one-half of these phases or steps have been completed. In
the current edition of the plan, two additional phases have been added for
research activities, neither of which has been funded.
Funds for expansion of the service were first received in fiscal year 1962
and continued to be made available for several years. However, since fiscal
year 1966, expansion of the service has been slower. In F. Y. 1968, four fire
weather meteorologists were added. No expansion has taken place since.
At present, two permanent fire weather meteorologists are assigned to the
program. This number is inadequate to cover an area the size of Alaska with
its varied climatic regime. Mr. Comiskey has told me that region head-
quarters is planning the temporary assignment of two or possibly three
meteorologists to the fire weather program, so there will be four or five
meteorologists working in the Alaskan fire weather service during the 1971
fire season. This arrangement uses funds and personnel diverted from other
service programs. There is no guarantee that the arrangement can be
continued.
A fire weather staff of five meteorologists is considered the minimum to
meet the needs of fire control agencies in Alaska. It will allow a 16-hour-day
coverage for fire weather and more detailed forecasts for smaller areas. It is
anticipated that the expanded staff will result in a significant increase in
service and quality of the forecasts.
As the last third of the field service program covered by the Federal Plan
for a National Fire Weather Service is implemented, three additional fire
weather meteorologists will be added to the permanent fire weather staff at
Anchorage, bringing the total to five. The temporary expansion in the service
during the 1971 summer season will provide an excellent pilot program for
the permanently staffed program outlined in the national plan.
Many changes have taken place since the national plan was devised, some
within the plan itself and others within the organization of the National
Weather Service. In the plan, there has been considerable revision in the
priority list-that is, a rearrangement of the order of implementation in the
remaining phases. Alaska has been given a much higher priority for the
additional perso:tmel than is indicated in the March 1967 edition. The re-
mainder of the plan is still valid though minor changes will be made in the
next printing.
A major and very important internal change has taken place within the
National Weather Service since the original plan was written. Full responsi-
bility for the field service programs was assigned to the several region head-
quarters. Final decisions on the location of personnel and changes in the
service program itself are now made by officials who are familiar with the
operating program and are in a position to consult directly with agencies and
groups using the service. The result has been a decided improvement in all
the National Weather Service programs, including the fire weather service.
Another major change is one brought about by technical progress in the
field of meteorology and by the requirement to make maximum use of
professional personnel. During the past year or so, the National Weather
Service has begun a complete reorganization of its forecast program which,
stated briefly, will concentrate its forecast programs in a single office in each
State. In those areas where this change has already been accomplished,
results have been as good or better than expected. The effect of this move in
Alaska is likely to be minimal since the Weather £ervice office in Anchorage
has always been the forecast center for the State.
It has been suggested that a mobile fire weather unit is needed for the
Alaska fire weather service. This is a small weather office, manned by a fire
weather meteorologist, which is taken to the site of a fire and set up near the
fire boss's quarters. The unit is equipped with two-way radio telephone,
radiofacsimile, and a set of portable weather instruments. Power is provided
by a small motor generator. Through the use of the communication equip-
ment, the forecaster receives the latest weather charts and other meteorolo-
gical information. These are used to prepare forecasts for briefing fire
control personnel. Mobile units now in use are made from camper shells and
are mounted on 1-ton pickup trucks. Such a unit would be unable to reach
many of the fires in Alaska. Mr. Comiskey has recommended that an air-
borne unit be developed. There are several approaches to the problem. At
the Boise Interagency Fire Center, an airborne unit is packaged in individual
units so that it can be transported by a relatively small cargo airplane or by
small helicopter. It uses a tent for sheltering the equipment and to provide
quarters for the meteorologist. The boxes used for packaging the equipment
become desks and worktables. Should a helicopter of sufficient lifting ability
be available, possibly a complete unit in one lightweight housing would be
more satisfactory.
-----------------·----
119
---· ··---·-·-·----
120
In summary, the size of the fire weather service has remained nearly
constant in recent years. We have been unable to implement any part of the
plan since fiscal year 1968. We still expect the Federal plan eventually to be
fully implemented with three fire weather forecasters added to the Alaska
complement. These additional fire weather forecasters should assure ade-
quate fire weather service for the forested areas of Alaska. A mobile unit, to
be procured as soon as funds become available, will bring the fire weather
office to the site of large fires.
r
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
A relationship between
National Fire Danger
Rating System spread index
and time-of-day
in interior Alaska
Abstract
Daily cyclic patterns in air temperature, relative humidity, and windspeed
cause variations in fire behavior. A relationship between time-ofday and
spread index was developed for four interior Alaska stations to predict
diurnal fluctuation in fire danger for planning fire control operations.
Introduction
Fire control planners schedule some activities on the basis of a 24-hour
planning period. For example, Bureau of Land Management fire suppression
operations in Alaska are governed by a policy statement that recognizes a
daily planning period (3):
Our policy is to control fires during the first work period. Each district will dis-
patch sufficient crew to control such reported class A, B, and C fires before the
start of the next burning period (1000 hours each day). For any fire that is not
controlled in the first work period, the fire boss will request sufficient forces to
control it before the start of the next work period.
An important planning input is fire behavior. Information relative to fire
behavior throughout the 24-hour period can be useful for "calculating proba-
bilities," a fire planning procedure widely taught, and less often used. A
concept as simple as constructing fireline faster than the rate of perimeter
increase may be applied. Success depends upon an ability to anticipate rate
of spread and judge resistance to control, so sufficient control forces can be
ordered to complete the control line. "Calculating probabilities" forces the
planner to systematically consider important factors.
Fire spread, measured by the National Fire Danger Rating System
(NFDRS) spread index, is only one of four phases of the basic structure of
the danger rating system (fig. 1). The spread index, a part of the NFDRS,
h tegrates the effect of several factors in terms meaningful to the fire plan-
Nonan V. Noste
Pacific Northwest
Forest and
Range Experiment Station
Forest Service, U.S.
Department of Agriculture
121
l
' ~-
'
122
RISK
FliASE
Source: (])
Significant weather or fuel elements to be identified and evaluated by continuing research.
Figure 1. Basic structure of the National Fire Danger Rating System.
SPREAD
INDEX
(TIMBE:R) Source: (])
Figure 2. Components of the spread phase of the National Fire Danger Rating System
used in interior Alaska.
ner. Components of the spread index, as applied in interior Alaska, are
dry-bulb temperature, relative humidity, and windspeed. The spread index
(fig. 2) integrates air temperature and relative humidity in a fine-fuel mois-
ture determination and then combines fine-fuel moisture and windspeed into
a fine-fuel spread index. Spread index is a number expressing the relative rate
of forward movement of surface fires.
In Alaska, as elsewhere, fire control plans are based on spread index, and
spread index can be assumed to follow a diurnal cycle. Spread index values
are related to time-of-day in the Intermountain States (6) and in the Lake
States (2). Fuel moisture percent, air temperature, relative humidity, and
dewpoint, and the burning index have been shown to follow a diurnal
pattern in Alaska (5). However, a relationship between NFDRS spread index
and time-of-day has not been developed for Alaska. The results of a study to
determine the diurnal pattern of spread index in interior Alaska are con-
densed in this paper.1
The Problem
Formalizing questions about the relationship between spread index and
time-of-day were helpful in designing an objective analysis procedure.
(1) Are there differences in the relationship in different climatic zones?
(2) Does the relationship change as the season progresses because of changes
in length of day? (3) Does the relationship change on days with extreme
burning conditions( The relation should be representative of days with
extreme potential for fires to spread, as well as of more "normal" or average
days. The following null hypotheses were established. The diurnal variations
in spread index do not change with:
1. Location
2. Season
3. Magnitude of the index
Methods and Results
Local climatological data published by the National Weather Service were
used as the data source for computing spread index. Summaries for Anchor-
age, Bethel, McGrath, and Fairbanks were obtained for April through July,
1957 through 1961. The stations are located in the transitional and con-
tinental climatic zones of Alaska (fig. 3), which are important fire zones. The
months of April through July cover the maximum of both man-caused and
lightning-caused fire occurrence periods (fig. 4 ). The years 1957 and 1959
were extreme fire years with 391 and 320 fire occurrences, and 5,049,661
and 596,574 acres burned, respectively. Only 44 fires and 5,100 acres
burned in the year 1961.
1 Study results are being reported to the Graduate School, University of Montana, Missoula, in a
master's thesis, "An Analysis of Diurnal Variations of National Fire Danger Rating System Spread
Index in Interior Alaska."
123
N ~
~
/ ~
////~
Southwestern
Interior
Basin
coNTINENTAL.
"f'FAIRBANKS
Coast
T I M E
~ 0 100 200
miles
SOURCE: (~)
Southeastern
Islands
Figure 3. Map of Alaska showing climatic zones and location of stations studied.
-----~~---~------------~----------
<I) w a: u:: ...
0
a: w
ID :::;;
:::> z
300 Source: (!_)
MAN-CAUSED FIRES ---
LIGHTNING-CAUSED FIRES----
200
100
/·'\. /\ x·' \
I • \
I IV''\ • I • '\, I I '\./·-·--·
• I \.._ ' __....-./ ........ l ................. ,,
OL-~1~-~11--~2~1-~1-~11~-~2~1--~1~-~11-~2~1-~1-~1~1-~21--~1~-~11--~2~1-~1-~1~1-~21~-~1~-~11~-~2~1-~1-~1~1-~21~--
10 20 31 10 20 30 10 20 31 10 20 30 10 20 31 10 20 31 10 20 30 10 20 31
MARCH APRIL MAY JUNE JULY AUG. SEPT. OCT.
Figure 4. Number of ftres by cause for 10-day periods, interior Alaska, 1956-65.
90
80
70
60
X .w
0 50 ~
0
<( w 40 a: a...
(f)
30
20
00 02 04 06 08 10 12
HOUR
14 16
HIGH ................
MODERATE ·--------
COMBINED
18 20 22
Figure 5. The relationship between spread index and time-of-day for four stations for
two seasons by class-of-day.
125
126
Selection of a sample of days for developing the relationship between
spread index and time-of-day was an important step. A similar study ( 4) in
northern Idaho used settled summer days, beginning on the fifth day in July
on which the burning index reached 30 or more, as the criteria for selecting
sample days. The criteria helped select days with diurnal variations typical of
days when fires were most likely. For similar reasons, two classes of days
were arbitrarily established to select days for this study. The basis for selec-
tion was the noon spread index, and the selection criteria were (1) moderate,
30-49, and (2) high, 50 plus.
The noon spread index was computed for each day. Spread index was
computed according to procedures outlined in the National Fire-Danger Rat-
ing System Handbook (7). Herbaceous stage was assumed to remain cured
throughout the year in accordance with local practice. Two days were then
systematically selected for each year-station-season-class category. Seasons
were defined as (1) April-May and (2) June-July. Total sample size was 2
(days) x 5 (years) x 2 (seasons) x 4 (stations) x 2 (classes-of-day), or 160
days. Spread index values were computed bihourly (0000, 0200, ... , 2200
hours) for each of the 160 sample days. Total number of observations was
160 days x 12 bihourly observations per day, or I ,920 observations. Analysis
of variance was computed with spread index as the variable of interest, and
hours, seasons, classes-of-day, and stations as factors. 2 There were no signifi-
cant differences in spread index between stations, seasons, or the inter-
actions of hours and seasons or hours and stations. This is reason to accept
hypotheses I and 2 and conclude that there is no difference in the diurnal
pattern of spread index between seasons and locations. A relationship based
on these results is termed "combined" and shown in table I and figure 5.
"Combined" means an average of the two classes-of-day.
2 Years were not considered as a source of variation, and inclusion as a factor in subsequent studies
may increase the sensitivity of the analysis of variance.
TABLE 1.-Bihourly spread index values for four stations and two seasons
Class-
of-day1 00
Hour
22
-------------------Spreadindex -------------------
High 18 15 14 19 29 41 56 51 48 45 38 26
Moderate 16 12 10 14 22 29 37 38 40 36 28 21
Combined 17 13 12 16 25 35 46 45 44 40 33 23
1High: Noon spread index= 50 plus.
Moderate: Noon spread index= 30-49.
Combined: An average of moderate and high.
------------------------------------·-------------
The interaction between day class and hours was significant. 3 This
difference can be seen by examining the relationships of high and moderate
classes in table 1 and figure 5. Spread index peaks at noon on high days and
at 1600 hours on moderate days.
. A sampling problem prevents interpreting the significant interaction be-
tween day class and hour as reason to reject hypothesis 3. The interaction
suggests there may be a different diurnal pattern associated with the general
level of the index. The selection criteria may have biased the sample toward
days with spread index peaks at noon. This puts a restriction on how general-
ly the relationships can be applied. The "high" and "moderate" curves repre-
sent the diurnal pattern only on days that fit the selection criteria.
Discussion and Conclusions
Our ability to interpret spread index in terms of natural rate of spread is
quite crude. Knowing the diurnal pattern can give the theoretical insight
necessary to understand fire behavior even though the numbers cannot be
interpreted precisely. Interest is more in the trend of the curve than in the
numerical value itself.
The relationship of spread index to time-of-day on "high" days contra-
dicts many fire _control people's assumption that spread index maximum
would occur near 1600 hours on all days. The fire planner assuming that
spread index will increase from noon to 1600 hours on "high" days is likely
to misjudge the fire control situation.
Users of the relationships presented in this paper should keep in mind the
data base from which they were derived. The curves do not represent an
average or "normal" day. The curves were derived for four stations in the
two climatic zones and should not be expected to hold in other zones. The
curves represent the April through July portion of the fire season. Season
and location results suggest the relationships may apply generally. Until such
time as relationships are derived using a broader data base, it may be neces-
sary to apply these curves. General application may be reasonable, consider-
ing that the information taken from one location, Priest River, Idaho, has
been interpreted to represent the entire Intermountain States area.
The relationships should help predict fire behavior during the 24-hour
period. This type of curves has broader application than planning control
operations. Resource managers need fire behavior information to evaluate
fire effects and to manipulate vegetative cover by prescribed use of fire.
Hopefully, the-relationships will also fill one of the information voids neces-
sary to define the role of fire in the northern environment.
3 F 11/1728 df= Z88 which is significant at the 0.01/evel.
-----------------------~-·----------------------
127
-------------------
-~----------------------------~--~---------~---------------------------------
128
Literature Cited
1. Barney, Richard J. 1969. Interior Alaska wildfires, 1956-1965. USDA
Forest Serv. Pac. Northwest Forest & Range Exp. Sta., 47 p., illus.
2. Brown, James K. 1964. Hourly variation in fire danger in the Lake States.
USDA Forest Serv. Res. Note LS-45, 2 p. Lake States Forest Exp. Sta.
3. Bureau of Land Management. 1970. Alaska State fire plan. U.S. Dep.
Interior.
4. Fahnestock, George R. 1951. Correction of burning index for the effects
of altitude, aspect and time-of-day. USDA Forest Serv. N. Rocky Mt.
Forest & Range Exp. Sta. Res. Note 100, 15 p.
5. Hardy, Charles E., and James W. Franks. 1963. Forest fires in Alaska.
USDA Forest Serv. Res. Pap. INT-5, 163 p. Intermountain Forest &
Range Exp. Sta.
6. Stockstad, Dwight S., and Richard J. Barney. 1964. Conversion tables for
use with the National Fire Danger Rating System in the Intermountain
area. USDA Forest Serv. Res. Note INT-12, 6 p. Intermountain Forest &
Range Exp. Sta.
7. USDA Forest Service. 1968. National fire-danger rating system hand-
book, FSH 5109.11.
8. Watson, C. E. 1959. Climates of the States: Alaska. Climatography of the
U.S., No. 60-49, 24 p. U.S. Weather Bur.
-----------------------------
----------~----~~--------------------------
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
Bureau of Land Management
computerized fire-danger
• rating system
Abstract
In 1967, the Bureau of Land Management in Alaska began producing
isoline maps of buildup index by hand on a daily basis. These maps proved
to be operationally valuable. In 1969, it was proposed that the isoline maps
and other fire-danger ratings be produced by machine. By the middle of
1970, a complete fire-danger rating package, including isoline maps, was
being machine-produced on a daily real-time basis and disseminated to a
variety of users within 4 hours of observation time. This paper describes the
system by which the data are processed, the form of the output, and the
method of dissemination.
The vastness of Alaska and the inaccessibility of many of its parts pose
many disadvantages, but in at least one respect, there is an advantage-its
vastness and inaccessibility tend to force one to make adaptations that might
not be considered elsewhere.
For instance, let us consider the problem of fire detection by looking at
figure 1. The area of most common occurrence of wildfire is the mainland of
Alaska-approximately 600 miles north and south and the same east and
west-comprising a total of 360,000 square miles. The area is too vast to
consider for a conventional fire detection system. Consequently the Bureau
of Land Management (BLM), which has the bulk of responsibility for fire
control within Alaska, has developed a rather sophisticated system of aircraft
patrol.
In addition to looking for fires, a major function of the patrol system is
thunderstorm detection and followup. On certain days, the thunderstorm
area is so large that a fleet of five aircraft, ranging from a Lear Jet to a
Cessna 180, cannot adequately cover it.
Furthermore, if a fire was detected-say near Kobuk-the closest smoke-
jumpers would be 300 miles away in Fairbanks. The closest retardant plant
would be in Galena-150 miles away. The fastest retardant aircraft we now
have, a PB4Y, would take 2 hours to make the round trip to the fire.
Albert L. Comiskey
Fire Weather,
National Weather Service
Anchorage, Alaska
129
' ~ -
130
In 1970, there were only 39 ,permanent BLM employees available and
qualified for fire duty. Consequently, 119 "seasonals" were hired last sum-
mer. Many emergency firefighters are scattered throughout the entire State
in small villages with access only by plane or boat.
Pre-positioning of men and equipment is being used more and more. Pre-
positioning can save millions, but it also can cost quite a bit. It is relatively
easy to see that we have problems that do not exist elsewhere. These prob-
lems forced us to adapt, and one of the adaptations was the isoline map of
buildup index, which evolved in the following manner.
The fire-weather unit in Alaska prepares and disseminates scheduled,
specialized, thunderstorm forecasts for patrol purposes. The BLM Division of
Aviation receives the forecasts via a fire-control teletype network. The patrol
coordinator frequently calls the fire-weather forecaster for additional
input-particularly vvhen the thunderstorm forecast area is large.
Since there were times when it was impossible to patrol the entire thun-
derstorm forecast area, the problem became one of how best to reduce the
patrol area (fig. 2). On numerous occasions it was suggested, by the fire-
weather forecaster, that the patrol be limited to the areas of high buildup
index-say 80 or higher. This suggestion brought to light a weakness in the
patrol planning-t~ere was no comprehensive depiction of the fuel moisture
pattern in the State. To overcome this, the fire-weather meteorologist sug-
gested that the BLM construct isolines of buildup index. This suggestion was
adopted; and a study course was prepared and a training session was con-
-------------~---·------------·
ducted to familiarize BLM personnel with procedures for preparing the
isoline chart, which was utilized by fire control operations beginning in the
summer of 1967.
In late 1968, Lowell King of BLM proposed that the fire-danger ratings of
buildup index (BUI), spread index (SI), fine fuel moisture (FFM), and condi-
tion class (CL) be handled by computer. The problem was presented to the
BLM Branch of Data Processing, and a program was written and run on an
experimental basis during the summer of 1969.
At that time, BLM had an in-house IBM 1130 Computer and an IBM 1627
Plotter. The programs are written in Fortran IV.
The first program, labeled WEA2, inputs the basic weather data required
for fire-danger rating computations. It computes BUI, SI, FFM, and CL for
individual stations, lists fire-danger ratings, lists past weather and past fire-
danger ratings upon call, and recomputes all fire danger ratings from point of
data addition, or correction, to latest data entry. Figure 3 shows the form of
the tabulated output.
As program WEA2 was being developed, someone suggested that it would
be nice if we could get the IBM plotter to do the isoline maps; consequently,
John Lambe, BLM Chief of the Branch of Automatic Data Processing, agreed
to write the programs necessary to make machine-produced isoline charts.
------------
E---
131
FIGURE 3.-Tabulated Output from WEA2.
ALL STATIONS
DAILY FIRE DANGER ACTUAL
STA PREC FFM BI SI CL
CIL 0.13 13.0 36 12 2
UNK 0.07 16.0 10 34 3
IAN 0.00 11.0 33 21 2
TAY T 30.0 31 1 1
BTT 0.11 10.0 22 25 2
GAL 0.02 13.0 12 33 3
HSL 0.06 13.0 27 23 2
KUK 0.12 10.0 7 27 2
TAL 0.28 10.0 31 37 3
UTO 0.02 13.0 15 20 2
CEM 0.03 8.5 24 23 2
EAA 0.17 9.0 33 35 3
FYU 0.17 10.0 22 22 2 svs 0.15 12.0 41 13 2
CIK 0.08 9.5 51 21 2
BET 0.40 30.0 5 5 1
ANI 0.33 16.0 5 22 2 ' c
' FWL 0.01 13.0 18 23 2 • ~ MCG 0.10 16.0 11 19 2 f
SLQ 0.15 30.0 76 1 1
BIG 0.15 8.0 42 49 4
FAI 0.05 8.5 34 47 3
ENN 0.21 9.5 36 33 3
ORT 0.13 9.5 18 28 2
TSG 0.00 5.5 40 66 4
SOF 0.00 8.0 38 39 3
AKN 0.06 16.0 22 34 3
KNW 0.26 12.0 11 41 3 svw 0.07 30.0 6 5 1
ILl 30 STA MISSING. 1 ADDED TO BI
ANC 0.00 9.5 25 44 3
BVD 0.00 12.0 59 21 2
CDV 0.26 15.0 4 8 1
GKN 0.02 7.0 50 69 4
HOM 0.03 30.0 42 1 1
ENA 0.01 15.0 32 18 2
LWG 0.00 15.0 30 10 1
SKL 0.00 15.0 59 14 2
UMM 0.22 11.0 7 44 3
TKA T 9.5 9 21 2 ;
WLA 0.00 9.5 11 14 2 ' i
MXY 0.00 12.0 12 11 1
ENN 0.00 10.0 18 13 2
ASO JENNINGS 8/6/70 1630 "
132
~--~
I
133
t-
134
Two additional programs were written, the first, labeled PUNX, reads
buildup index values from the disk as computed by WEA2. It also computes
BUI values at "dependent data points."
Most of the observation stations in Alaska are along the coast or along the
rivers. There are very few stations in the mountains or even in the hills. You
will note that Station ZSl (fig. 4) is over a range of low hills called the
Killbuck Mountains. These are not much compared with what we normally
think of as mountains in Alaska, but there are numerous rounded peaks as
high as 4,000 and 5,000 feet, and they cover quite an area. There are no
observations from this area. A group of fire-weather and fire-control people
got together and hypothesized what the fuel moisture and fire-danger ratings
might be in that area, based on experience, past fire history, etc. The group
came up with the following formula for Z51 (fig. 5).
Note that Z51 is a function of Z 16 and Z33. In fact, Z51 is one-half of
the averaged values of Zl6 and Z33. Other formulae were derived for other
locations.
PUNX also punches cards of buildup index values. These cards and data
are required as input to the next program, POSTW.
POSTW inputs the data from PUNX off the punched cards and plots the
buildup index on the isoline map. It then calls the contouring package,
"NUMERICAL SERVICES TECHNIQUES IBM 1130 CX llX CONTOUR
PACKAGE VERSION 2." The contour package completes the job. Figures 6
and 7 are examples of the completed product.
Map
~~"'-""---_LJ..L 1500hrs.ADT
TI\UE AT &tt N.
" 0
135
136
Note on these completed isoline maps that the program has plotted data
values of zero over the major mountain ranges and over large bodies of
water. This is based on the premise that buildup index values are always zero
over snow-covered areas and over large bodies of water. Let us take the
computer-produced isolines and transpose them to a map where the topo-
graphic features are more evident (fig. 8).
Notice how, with the help of the hypothetical data points and the fixed
zero values, the computer takes into account topography, and to a certain
extent, climatology, since climatology was subjectively estimated when con-
structing the formulae for the hypothetical data points.
In many respects, the computerized fire-danger rating system can be
improved upon; but even if it were perfect, its value would be greatly re-
duced if there were no effective method of disseminating the output. The
tabulated data are disseminated on a real-time basis by the BLM teletype
network for fire control and by Service 0-Federal Aviation Administration
aviation circuit. The BLM circuit is shown in figure 9.
Service 0 is a national circuit, and its function, in this case, is to transmit
the data to the Boise Interagency Fire Center in Boise, Idaho.
The isoline map is transmitted on Intra-Alaska Facsimile (fig. I 0). It is
also transmitted by telecopier to Boise, Idaho. And finally, it is transmitted
by messenger to the BLM Division of Aircraft in Anchorage.
For system evaluation purposes, the following factors should be con-
sidered:
1. VOLUME. The system becomes more efficient with added volume since
the time to set up and discontinue the run remains the same. The time
difference in computations and printout between low and high volume is
negligible.
2. ECONOMY. At this stage, I believe that no money is saved in man-hours
. unless recall and correction are involved or if the volume increases.
3. RELIABILITY. Near maximum.
4. RECALL AND CORRECTION CAPABILITY. Far superior to hand
methods.
5. RECORD STORING. Excellent, except not as accessible as hand method.
6. REAL-TIME ASPECTS. Fair. An experienced individual can produce
about as fast as the machine, but the individual cannot produce any
significant increase in volume.
7. IMPROVEMENT POTENTIAL. Considerable. Overall, I would evaluate
the present system as good. In addition, it provides an excellent backup
and check of the hand system.
~-
-
L
~ --
137
138
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Weather modification-
a fire control
tool
Abstract
The application of weather modification techniques as a fire control tool
was field tested in Alaska during the summers of 1969 and 1970. The 1969 trial
was primarily exploratory. Data gathered indicated clouds or cloud-systems
exist in interior Alaska which are amenable to current cold cloud modification
techniques and could be used in fire control. Based upon these data and results
obtained during 1969, a full-scale field trial was designed and conducted during
June and July of 1970. Organization of the project, equipment, and facilities-
as well as the imposed constraints-are discussed. Results show cloud seeding
can be an effective fire control tool when the proper meteorological condi-
tions exist. The potential is great if application can be made under these
conditions. However, like any tool, weather modification techniques can
only supplement other fire control techniques already in use.
The summer of 1969 presented the worst fire siege in Alaskan history.
The combination of a series of unprecedented dry seasons extending through
two summers and the 1968-69 winter had set the stage. An abundance of dry
lightning storms in tum had added the key ingredient of ignition. In a
description of the situation early in June of that year, the Bureau of Land
Management (BLM) said,
Alaska is currently experiencing a most severe fire season, due
to extremely dry conditions and occurrence of dry lightning
storms. Over 3 million acres have been burned since January 1,
1969. It is considered that an extreme emergency situation exists
in Alaska at this time.
Grasping at every means of alleviating the problem, the Department of the
Interior surveyed the capabilities of its various agencies and considered with
new interest the Bureau of Reclamation and its Project Skywater-a scien-
tific research program of cloud seeding to augment precipitation in water-
short areas of the Nation.
William J. Douglas
Division of
Atmospheric Water
Resources Management
Bureau of Reclamation
Department of
the Interior
Denver, Colorado
139
140
~-·--------~-··-----·······----------------------
The question, "Could cloud seeding be employed in fire control in the
existing emergency?" was asked of Dr. Archie M. Kahan, Chief of Project
Skywater. His response, conservatively phrased, was that cloud seeding
should not be ruled out, that there are some possibilities which hold
promise; however, evaluation of results would be most difficult. Following
additional discussions, the Bureau of Land Management decided to go ahead
with a short trial period during July and requested technical assistance from
Dr. Kahan's staff. I was given this assignment.
Officially named Project MOD, the staff consisted of personnel drawn
from the Weather Bureau, the Forest Service, the Bureau of Reclamation,
South Dakota School of Mines and Technology, and EG&G, Inc. (the seed-
ing contractor), in addition to personnel from BLM. Organization of the
MOD Squad, as it came to be known, was headed by Mr. James Richardson,
BLM's Chief of Fire Control for Alaska. In addition to support elements, the
MOD Squad contained three major groups-the Weather Advisory group
(WAG), the Field Evaluation Group (PEG), and the seeding contractor
(Appendix 1). Equipment included both high-and low-level observational
aircraft, a helicopter for PEG transportation, an infrared-equipped aircraft,
and the seeding aircraft. Arrangements were made to use a program from the
Project Skywater library for analysis of soundings by the University of
Alaska's computer center and to employ U.S. Air Force radar for cloud
observation. The field experimental period was 1 0 days from July 24
through August 2 of 1969.
Seeding was to be conducted with pyrotechnics fired vertically from the
aircraft at the level of -1 0° C. down through the cloud. Each round would
release 30 grams of silver iodide. The number of rounds fired would be
determined by direct observation from the seeding aircraft.
The objective of the project was to produce precipitation on forest fires in
Alaska. To accomplish this, a going fire was designated as the target; a
suitable cloud or cloud-system which would move over the target was
selected and seeded to produce the maximum precipitation on the target.
Evaluation was to be made by the PEG whose members would be located
on the target fire and would accumulate data using belt meteorological kits,
time-lapse motion picture cameras, and visual observations. The infrared-
equipped aircraft would scan the target prior to and after precipitation.
Radar observations of the selected cloud or cloud-system would be made.
Visual and photographic observations would be made from all other aircraft.
Fundamental requisites for the operation are, first, a target fire and,
second, meteorological conditions which will produce clouds amenable to
modification by cold cloud modification techniques.
With the existing fire situation in July 1969, finding a target fire was no
problem. Suitable meteorological conditions during the 1 0-day operational
period, however, did present a real problem. During this period, the weather
conditions which existed were marginal to unsuitable for cloud seeding.
Operations, all conducted in the Fort Yukon area, appeared to stimulate
precipitation on 2 days and rain fell on or near existing fires, producing a
detectable suppressive effect. A summary of the operations is shown as
Appendix 2.
The conclusions, as stated in my report to BLM, contain the following
comments:
In assessing the potential of weather modification techniques
for a particular purpose, two-factors are ofprime importance:
1. Are the clouds/cloud systems suitable for modification?
2. If modified, will the resultant increase in precipitation
produce the desired effect?
Based on the results of Project Skywater research programs
extrapolated to Alaska and meteorological observations made
during Project MOD, clouds/cloud systems which occur in
Alaska appear to be suitable for modification by cold cloud
techniques.
This conclusion, coupled with information gained from dis-
cussions with BLM and Forest Service fire control personnel
concerning the amount of precipitation required to produce a
beneficial effect, indicate a potential does exist for the employ-
ment of weather modification techniques in Alaska for fire
suppression, control, and especially fire pre-suppression.
Recommendations included consideration of an extended operational
period to begin earlier (before July) and continue for at least 30 days.
Based upon the results of the 1969 program, the BLM decided to carry
out a second operation during the summer of 1970. This project, however,
was conducted for a 60-day period from June 1 through July 31. An
expanded staff and supplemental equipment were employed, and an
advanced computer model was run on the University of Alaska's computer
to refine the operational phase and provide a more definitive evaluation.
The primary objective was to seed clouds over or near wildfires to induce
rain in amounts which would be beneficial to fire control. The primary
project area was circular with a 50-mile radius around Galena where the
operational equipment and field personnel were based. An extended area of
operations, within 200 miles of Galena, was an option, as were similar
circular areas of 50-and 200-mile radii with Fort Yukon as the center.
Should the Fort Yukon areas be used, Fairbanks was to be the operations
base. Overall meteorological support and project direction were from Fair-
banks in all cases.
The project staff organization again consisted of three major elements-
the weather team, the fire and fuel team, and the contractor (Meteorology
Research, Inc.).
141
142
Project headquarters was established in Fairbanks where the project
leader, two members of the weather team, the contractor project manager,
and support personnel were based. Also based in Fairbanks were the high~
level observation and control aircraft and an aircraft equipped with infrared
cameras.
At Galena were the flre and fuel team consisting of the team leader, seven
observers, a low-level observation aircraft and pilot, two helicopters and
pilots, one member of the weather team, the contractor field operations
group (consisting-of the-field manageF,-rawinsonde, and operator), the radar
and operator, and the seeding aircraft and pilot. The project organization is
shown as Appendix 3.
In order to determine areas suitable for cloud seeding, daily analysis of
weather information, both surface and aloft, was required. Upper air sound-
ings from appropriate available Alaskan stations were needed, and additional
upper air characteristics in the vicinity of Galena were necessary for more
detailed analysis. A numerical computer model utilizing this upper air
information and a computer facility were additional tools used to assist in
the determination of conditions suitable for cloud seeding.
To properly evaluate the effectiveness of cloud seeding for retarding fire
spread, ground observations and measurement of precipitation produced
were needed, and information on the reaction of fine fuels to the precipitation
was desirable. The use of radar for tracking seeded clouds and aircraft visual
observations of seeding effects, precipitation tracks, and effects on fires were
included in the operation.
In addition to the excellent logistics and technical assistance from the
BLM Fairbanks District Office and Fairbanks District Operations, the sup-
port from the Weather Bureau's Fire Weather Office, the Forest Service's
Forestry Sciences Laboratory, and the University of Alaska computer center
provided significant and necessary inputs.
The FAA flight service station at Galena provided teletype weather
information from Service "A" and "C." It was used by the project radar
meteorologist for weather analysis and subsequent project briefing for the
field team leader and flightcrews on a daily basis.
The scientific basis for seeding cumul.us clouds to produce increased rain-
fall has evolved considerably since the first experiments in 1947. It was
thought that the principal role of artificial ice nuclei in cumuli was to trigger
the Bergeron rain mechanism. As seeding experiments became more com-
mon, it was found that the dominant effect of the artificially produced ice
crystals in cumuli was not to initiate the Bergeron mechanism but rather to
increase the vertical extent of the clouds. The heat released by freezing the
supercooled water in cumuli is often enough to double a cloud's buoyancy
and trigger vertical growth in several thousand feet. This increased vertical
growth will generally increase the cloud's precipitation by intensifying the
circulation in the cloud, thus causing the cloud to process more water vapor
into liquid water. Until recently, very little mention was made of increasing
the horizontal dimensions of the cloud.
As a result of experiments carried out in Flagstaff, Arizona, under Bureau
of Reclamation sponsorship and by National Oceanic and Atmospheric
Administration (NOAA) in the Caribbean, it is now clear that under some
conditions the horizontal growth of cumuli is more important than the
vertical growth. If, through judicious seeding, one can double the horizontal
dimensions of the cloud, the precipitation can be increased by a factor of 8
to 10. A doubling of precipitation was considered maximum when only
verticle growth was hypothesized to occur due to seeding.
It is clear from these experiments and others that horizontal growth re-
sulting from seeding does not occur as rapidly as is the case with vertical
growth. The first phase is a pronounced vertical growth. If the seeding is
continued, the heat released within the cloud by the freezing of supercooled
water serves to organize the cloud updrafts into one coherent core, through
which a new surge of moisture is drawn. It is with this new moisture surge
that the horizontal dimension of the cloud is increased.
With these concepts in mind, the seeding procedure should involve tech-
niques to induce vertical growth first, and then horizontal growth. There are
two techniques that have been successfully employed to increase the vertical
dimension of cumulus clouds through airborne seeding. The first technique,
employed in the Caribbean and at Flagstaff, uses vertical-fall silver iodide
pyrotechnics. These devices are fired into the top of a rising cloud turret as it
passes the -1 0° C. level. The technique has the advantage of making certain
that the seeding material enters the supercooled region of the cloud and that
it arrives there at the correct time. This technique is best used on relatively
small clouds that cannot be made to grow horizontally and on somewhat
larger clouds to spur the vertical growth phase mentioned earlier.
The second technique of airborne seeding has been successfully used in
Flagstaff, Arizona, and elsewhere. It involves below-cloud seeding with either
an acetone-silver iodide mixture or silver iodide pyrotechnics burned from
the wing of an airplane. This technique has the disadvantage of relying on
the cloud updrafts to advect the seeding material into the supercooled region of
the cloud. If the updrafts are weak or intermittent, the technique cannot
work, as the material will not reach the supercooled region of the cloud at
the right time in the cloud's lifetime.
The below-cloud technique has some distinct advantages, however, when
the cloud has a strong, persistent updraft. Under these conditions, the
material is advected into the right parts of the cloud, over an extended
period of time, and over the whole width of the updraft core. This time and
space spread of the seeding material fosters the horizontal as well as vertical
growth of the cloud.
The seeding aircraft was equipped to employ both techniques and used
both methods during seeding. The choice of which technique to use was
143
144
.~~~~~~~~·---~---~~~-~--
based upon advance numerical model calculations and visual observations of
the response of the clouds during the operations.
A version of the Weinstein-Davis numerical cloud model was used with the
University of Alaska IBM/360-40 computer. This model combines the
accuracy of detailed calculations, where the cloud mechanisms are well under-
stood, with the speed of parameterization where the phenomena are
complex, and was produced for use as a field operations tool.
The computer program is divided into two main sections-interpolation
and model computation. The interpolation section takes a standard radio-
sonde sounding of pressure, temperature, and relative humidity, at
mandatory and significant levels starting from observed or calculated cloud
base. This sounding is expanded to equally spaced vertical intervals. In this case,
200-meter intervals were applied. The computation section of the model
included the thermodynamics, cloud physics, dynamics, and auxiliary
calculations.
A full range of cloud sizes from 0.5-kilometer radius to 5.0-kilometer
radius, each with ice nucleation temperatures of -8° C. and -25° C., was run
through the model in order to define the size of cloud, if any, most suscepti-
ble to seeding. The increased height of cloud top and increased amount and
duration of precipitation were then used as a basis for comparison with the
analysis of other weather information to determine the probability of effect-
ing cloud seeding within the operating areas. In general, an increase in cloud
top height of about 3,000 feet and an indication of 0.1 inch or more of rain
on the ground were the criteria used to determine suitability for seeding.
Mathematical modeling of cloud processes was performed daily using the
Galena upper air sounding. When appropriate, based on analysis of current
weather patterns, one or more other soundings in or near the operating area
were also used.
In order to determine the probability of suitable cloud seeding weather
within the operating area on both a current and a forecast basis, certain data
were considered to be most desirable. Of particular importance was the need
for daily upper air sounding data from stations in or near the area, which
would be representative of the airmass characteristics within the area. Upper
air soundings were available at the Fairbanks fire weather office on teletype
service "C" from six reporting stations surrounding the area. A project
rawinsonde unit was installed at Galena to fill the gap in the regular station
network, and the sounding information was transmitted to the project Fair-
banks office via BLM teletype. Synoptic surface weather observations and
500-millibar data were also available at Fairbanks, and daily surface and
500-millibar charts were plotted and analyzed each morning. At Galena, an
additional streamline (windflow) analysis over Alaska was made using the
12,000-foot winds. Early observations of cloud depth and movement in the
project area indicated that this level of windflow could be used for an initial
estimate of cloud movement for operational preflight planning and briefing.
Facsimile weather charts received from the national network and from the
Anchorage Weather Bureau office were also used on a daily basis, primarily
as extended forecast tools. Hourly surface observations from Alaskan sta-
tions were received in Fairbanks and were particularly useful in forecasting
maximum temperatures in the area to determine the likelihood and starting
times of convective cloud activity.
The weather radar at Galena was used primarily as an operational tool to
track and obtain the speed and direction of movement of cumuliform
clouds. Additional information on location and severity of storms which
could cause lightning strikes was obtained and relayed to the Galena fire
control office to aid in establishing patrol areas.
The operational procedures and routine established at the beginning of the
project were varied only slightly throughout the 2-month operating period.
The responsibilities and functions of all personnel were established to pro-
vide an operational capability 7 days a week. The basis for each day's activi-
ties was then the collection and evaluation of current and expected weather
and fire conditions, to determine if seeding operations would be conducted.
For the purposes of this project, an "operational day" was defined as one in
which operating area weather conditions existed, or were forecast, and were
conducive to cloud seeding to induce precipitation; and one or more fires
were going in this same area. It was emphasized by BLM that seeding efforts
"must be directed toward providing timely precipitation at critical points
either directly on a fire, or immediately ahead of the fire line, and in suffi-
cient quantities to effectively aid in suppressing the fire. The mere produc-
tion of rainfall without regard to location is not desired." The criterion for
defining "sufficient quantities" was established as 0.1 inch or more of
precipitation on the ground as forecast from available data, using the com-
puter model output as a guide.
An outline of the typical daily routine is as follows:
Project Schedule
0400-Weather data received at the Fairbanks weather office were plotted
0800 and analyzed by the weather team to provide current information on
weather conditions throughout Alaska, with primary concern for the
assigned operating areas. Prognostic facsimile weather charts were
collected and reviewed. At Galena, the rawinsonde team took the
upper air sounding and transmitted the data via teletype to Fairbanks.
0700 The upper air sounding from Galena, received on the BLM teletype
circuit, was plotted and analyzed for stability and moisture character-
istics. This sounding and one or more others from representative
stations near the operating area were transcribed into IBM punchcard
format and delivered to the University of Alaska computer center
about 0730. The cloud model program was run on the University
computer and the generated output returned to project headquarters.
At Galena, the radar meteorologist plotted and analyzed the sound-
ings and prepared the 12,000-foot-level streamline analysis. Aircraft
--------·------~----------------
145
146
~~~-~~~------~~-------------·--
were preflighted and,equipment readied for the day's operation.
0800 Fire condition reports were discussed with district fire control
personnel.
Project headquarters personnel were briefed on weather and fire con-
ditions for the current day. Forecasts were presented for the ensuing
3 days. A decision was made at this time on the day's operation and a
message (see example below) transmitted to the Galena base giving a
"weather summary," and, if appropriate, the "seeding data." Weather
-and -operational-briefings we-re also -com:lucte-d daily-at Galena. by-the
radar meteorologist and the fire and fuel team leader.
WOO-GAL Weather Summary
SURF ACE-E-W TROF OVERLIES CENTRAL ALASKA BETWEEN THE
BROOKS AND ALASKA RANGES. RIDGE ALONG EAST GULF COAST
NORTHWESTWARD TO COOK INLET.
500MB-LOW CENTERED OVER BRISTOL BAY. LIGHT TO MODER-
ATE SOUTHEAST TO EAST FLOW OVER THE STATE.
STABILITY-CONDITIONALLY UNSTABLE.
FORECAST TODAY-MOSTLY CLEAR BECOMING PARTLY CLOUDY
AFTERNOON WITH TCU, RW, AND TRW.
TOMORROW-INCREASING CLOUDINESS, SCATTERED RW.
OPERATIONS-GO.
SEEDING DATA
TARGETS-FIRST HUNGER 9633, SECOND OCTOPUS 9618, THIRD
DAKLIA 9601.
CLOUD BASE-4000 FT.
-10C LEVEL-13000 FT.
MIN CLOUD DIAMETER-2¥2 MILES.
UNTREATED CLOUD HEIGHT-14500 FT.
TREATED HEIGHT INCREASE-5500 FT.
RAIN AMOUNT TREATED-0.12 INCHES.
RAIN DURATION TREATED-16 MINS.
CONVECTION WILL BE INITIATED AT 1100 WITH SURFACE TEMP
OF 63F,
START SEEDING 1200
WOO-FAI WJD 7/15/70 0915
R DWH WOOGAL
0900-If weather and ftre conditions were suitable for a seeding operation
1000 and an operational day declared, the Fairbanks-based high-level air-
craft proceeded to Galena with the project leader, weather team
leader, contractor project manager, and photographer. When time
permitted, an operational briefing was conducted at Galena for all
participating personnel.
11 00-On operational days, an additional upper air sounding was taken at
1500 Galena at the time operations were being conducted and radar track-
ing and assessment were in progress.
1500-Oh completion of flight operations, a debriefing was held at Galena
2000 for all participating personnel. The project headquarters staff re-
turned to Fairbanks and reviewed the forecast weather and fire condi-
tions for the following day.
Operations
During the month of June 1970, there were 12 days in which the weather
was suitable for cloud seeding in the Galena area. On 7 of these days, there
were no active fires in the area (Appendix 4). Of the 5 days in June on which
frres occurred in this area, operations were conducted on 4 of these days-
June 11, 14, 16, and 30. On June 29, the area northeast of Galena in the
vicinity of the fires did not have suitable seeding weather.
During July 1970, fires became numerous in the area north and east of
Galena early in the month and a few were still in mopup on July 31
(Appendix 4). Weather in this area was operationally suitable on only 4 days
during this period, and seeding operations were conducted on these days.
Two additional operations were conducted under marginal weather condi-
tions for a total of six during the month.
A summary of the weather during June and July is shown in Appendix 5.
On July 20, the seeding aircraft and crew, plus one ground crew team and
helicopter, were moved to Fairbanks and the operating area extended, opera-
tions then to be conducted within 200 miles of Galena and the area from the
north slope of the Alaska Range to the south slope of the Brooks Range and
east to the Canadian border. During the last 10 days of July, there was only
1 suitable seeding day in this extended area, and there were no fires in the
area of the weather.
An operations summary covering the pertinent information on the 11
operational days flown is shown as Appendix 6.
The best results in terms of precipitation on fires were observed on June
11 and July 4.
~---~---·~--···-----~~~~-·-----------~--------------
E__
~-
147
148
On June 11, seeding weather was favorable in the Ganes Fire area. A cloud
about 8 miles upwind of the fire was seeded with two vertical-fall, silver
iodide pyrotechnics followed by one slow-burning flare. Cloud growth was
observed from the high-level aircraft with the cloud top going from 12,000
feet to 20,000 feet within 1 0 minutes of seeding. This compared favorably
with the computer model prediction of a 7 ,000-foot height increase due to
seeding. The seeded cloud was observed to move over the fire with rain
estimated by the fire boss to be about 0.25 inch on the fire. The morning
computer prediction was 0.1 inch or more. There appeared to be no other
suitable clouds in the fire area at the conclusion of the above operation.
On July 4, approximately 96 fires were burning in the Galena area. The
high-level aircraft flew a reconnaissance mission in the vicinity of the Daklia
fire and when suitable seeding conditions were observed to be developing,
the seeding and observation aircraft were called out. Three clouds were
seeded upwind of this fire, and the rain produced appeared to cross the
north end of the frreline, knocking down the fire in that area. The morning
computer prediction for the Galena area indicated cloud height increases of
10,000 feet and 0.25 inch of precipitation. Observed growth was estimated
at 8,000 feet. The afternoon Galena sounding and computer analysis, taken
during seeding operations, predicted cloud growth of 7,000 feet and 0.25
inch of rain with a 2-mile-diameter cloud. Enroute back to Galena from this
frre area, the ground control aircraft and seeding aircraft discovered a new
fire of about 10 acres which was later designated Star Fire No. 9615. Four
clouds upwind of the frre were seeded and produced rain on the fire. This
frre went from a fast-burning condition with flames and considerable smoke
to a smoldering condition.
On four of the other operations (June 16, July 3, July 7, and July 15),
results appeared to be only marginal. In each situation, the rain from the
seeded clouds either could not be verified as falling on the fire or was
observed to fall some distance away. On 3 of these days (June 16, July 3,
and July 15), the morning computer prediction indicated growth of about
5,000 feet with 0.1 inch or more of rain. However, by the time of the
afternoon sounding, the computer run predicted little effect from seeding,
verifying the observed weather during the operations. On the other day, July
7, the Galena sounding indicated no effect from seeding, although the oro-
graphic effect in the northern operating area did in fact set off some activity
which allowed a seeding opportunity.
On June 14, the seeding operation in the Rennie Fire area was undertaken
even though clouds in the vicinity of the fire were small. This seeding pro-
duced no effect on the clouds treated and no rain occurred.
On 3 other operational days (June 30, July 2, and July 5), the aircraft
were launched for fire areas, but seedable clouds were at distances of 10
miles or more from the fires and not moving in directions to affect the area
near the fire. The computer prediction on July 5 indicated no seeding effect,
and aircraft were launched on request from fire control. On July 30 the
--~--~-------~---------·-------~---~--
computer run in the morning was favorable, but afternoon weather in the
fire area had changed to dry, also indicated by the afternoon computer
output. On July 2, the morning Galena sounding and computer run showed
some increase from seeding, but suitable clouds in the fire areas were 1 0 to
15 miles distant.
Summary
The original plan of operation called for radar coverage and location of
the fire and fuel team on target fires for which seeding operations were to be
conducted. These procedures were based upon operations within the primary
operations area of about 7,500 square miles in a circular area of 50-statute-
mile radius around Galena. Unfortunately, no fires which could be acted
upon in this manner occurred within this primary operations area, and the
data which would have been obtained from the radar and the fire and fuel
team were not realized. In their absence, subjective observations became the
only basis for evaluating the effectiveness of cloud seeding as a fire control
tool.
As was stated earlier, the conduct of a cloud seeding operation for fire
suppression depends upon two basic factors: the existence of a fire and
weather conditions in the immediate fire area which will produce cloud
formations suitable for modification. A review of these two factors during
June and July reveals a total of 16 days in an area of 200 miles radius around
Galena during which weather conditions were suitable for modification oper-
ations. Of these days of potential operation, on 9 there were no target fires
available, thus eliminating approximately half of possible test days. On
approximately half of those days when both target fires and suitable weather
existed, suitable clouds did not exist in the immediate vicinity of the target
frre(s), thus further reducing the number of test cases.
Based on subjective observations, beneficial fire suppression resulted from
cloud modification on 2 separate days on three separate fires.
With the limited number of test cases, a firm conclusion as to the value of
weather modification operations in fire suppression cannot be made. In my
opinion, when the proper conditions exist, cloud seeding can be an effective
frre control tool. However, like any tool, these techniques can only supple-
ment other fire control techniques already in use. The potential is great if
the application can be made under the proper conditions.
-----·-------~---
---~-~-----
149
---·---------
-Vl
0
I
Administration
!HUT' ,,.,,,"111'
Appendix 1
PROJECT MOD ORGANIZATION-JULY 25, 1969
Contractor's Authorized Representative
I
I 1 I I I
Weather Field
Advisory Contractor Evaluation Photographyr Safety
Group Group
Lear Jet N 613 W Queen Air Commander 57E
Queen Air (IR) N5052 PH 1100 Helicopter
149Z N435 PH
I' "'O"ll'f',!~f]•f'l''-f~ )>I ('•1'11 'I 111 1·,-~--l' f1~1lfllf'lfllf!IP'"l(·l-!IQ' --n 'I i:l['ll "'f·li".tl
......
Vl
Appendix 2
PROJECT MOD SUMMARY REPORT
Day
no.
2
3
4
5
6
7
8
9
10
7-24 No Go
7-25 No Go
7-26 Go
7-27 No Go
7-28 Go
7-29 No Go
7-30 Go
7-31 Go
8-1 Go
Target
Two segments of
western perimeter of
9406, 10 miles east of
Fort Yukon.
Targets on north side
9406 along Porcupine
River, 25 miles NE.
of Fort Yukon.
Fort Yukon, Chandalar,
Stevens Village area
patrolled, none selected.
Fires on north side 9406
along Porcupine River
from Fort Yukon to
Shuman House.
Fire 9544 and west
end 9406.
8-2 No Go Stratified layers
with light rain.
Overall
weather
outlook
Low stratus, light ram
Small scattered cumulus
2,000 feet thick
Cumulus with broken
cloud cover
Stratiform with light rain
Cumulus embedded in
layer clouds, light
showers in area
General stratiform clouds
Flat cumulus 2,000
feet thick
Fiat cumulus 4,000
feet thick
Stratified layers
with numerous breaks
*Cloud seedability rating scale (estimated):
No.
0
I
2
3
4
Growth potential
None
Very low
Low
Moderate
Good
Top increase after seeding
0
'r '
0
2,000 feet+
5,000 feet+
10,000 feet+
i'
Remarks
Lear Jet reconnaissance showed general cloud cover
except broken in Bettles area. Many smokes on
9534 and 9406.
14 2 Light rain on Code 3 rain east of target on east part of 9406.
part of north Rain also on 9539.
25 2
0
22
42
target
2
Light rain
on target
0
0
**Rain intensity code (pilot's view):
0 None
1 Virga ,
Mission called off due to low ceilings and icing.
Difficult to distinguish seeding effect
from local showers.
Lear Jet patrol observed small cumuliform clouds in
Bettles area in late afternoon.
Flew reconnaissance of fires 9406, 9578, 9544.
No seedable clouds.
Clouds dissipated.
No rain observed near target.
2 Light-rain reaching ground; can easily see through
3 Moderate-see through with difficulty
4 Heavy-cannot see through
,.,r, -,, ·-~'1r;""lfl11'rrprT""'!'' '·I "]1""'" n ru.·n,,,,., -·w' J l''i
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N
~
~
~
Cll
C')
> ~ >
Appendix 3
BUREAU OF LAND MANAGEMENT 1970 ALASKA CLOUD SEEDING PROJECT ORGANIZATION
Weather Team Leader
BurRec
Meteorologist, USWB
-I Project Leader
BLM
Jl IR Aircraft I
Cessna 310 I
Photographer, BLM i I
I Contractor
I Project Manager
High Level
Control Aircraft
Merlin II
Secretary, BLM
----------------------------------------·
Radar Meteorologis
USWB ~---1
Team A
3 Observers
BLM-USFS
Helicopters
2 FH1100
Fire & Fuel Team Leader, l BLM
TeamB
3 Observers
BLM-USFS
Ground Control
Aircraft
Aerocommander
Dispatcher
BLM
~q-f'l ,,,r· 1 1'
Contractor
Field Manager
Contractor I I Contractor
Rawinsonde I I Radar
Contractor
Seeding Aircraft
Cessna 414
J
Appendix 4
Weather and Fires
Galena Project Area
June 1970 -
Date Seeding Weather Fires
6-1-70 Not suitable None
6-2-70 Not suitable None ~
~ 6-3-70 Not suitable None \
6-4-70 Not suitable None
6-5-70 Not suitable None
6-6-70 Not suitable None
6-7-70 Not suitable None
6-8-70 Not suitable None
6-9-70 Not suitable None
6-10-70 Operational-Galena None
6-11-70 Operational-Galena McGrath (Ganes-9215)
6-12-70 Operational-Galena None
6-13-70 Not suitable None
6-14-70 Operational-Galena McGrath (Rennie-9221)
6-15-70 Not suitable None ~-
6-16-70 Operational-Galena east Galena (Roundabout-9533)
6-17-70 Not suitable None
6-18-70 Not suitable None
6-19-70 Not suitable None
6-20-70 Not suitable None
6-21-70 Operational-Galena None
(high terrain)
6-22-70 Operational-Galena None
(high terrain)
6-23-70 Operational-McGrath None
6-24-70 Operational-McGrath None
6-25-70 Operational-McGrath None
6-26-70 Not suitable None
6-27-70 Not suitable None
6-28-70 Not suitable None
6-29-70 Operational-McGrath Galena (Hog-9571,
Not suitable-Galena east Hot Springs-9569)
6-30-70 Operational-Galena east Galena (Hog-9571)
153
Date
7-1-70
7-2-70
7-3-70
7-4-70
7-5-70
7-6-70
7-7-70
7-8-70
7-9-70
7-10-70
7-11-70
7-12-70
7-13-70
7-14-70
7-15-70
7-16-70
7-17-70
7-18-70
7-19-70
7-20-70
7-21-70
7-22-70
7-23-70
7-24-70
7-25-70
7-26-70
7-27-70
7-28-70
7-30-70
7-31-70
154
Appendix 4 (Continued)
Weather and Fires
Galena Project Area
July 1970
Seeding Weather Fires
Not suitable None
Operational-Galena East Several (approximately 40)
Operational-Galena Many (approximately 100)
Operational-Galena Many (approximately 70)
Not suitable Many (approximately 50)
Not suitable Many (approximately 50)
Not suitable Many (approximately 50)
Not suitable Many (approximately 50)
Not suitable Several (approximately 15)
Not suitable Several (approximately 15)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Operational-Galena Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Not suitable Few (mopup) (approximately 10 or less)
Appendix 5
Weather Summary-June-July 1970
June
During the first week of June, a 500-millibar (mb) low was located off the
eastern Arctic Slope with a strong ridge over eastern Siberia. A dry northerly
flow of stable air made cloud seeding impossible. At the end of the first
week, a major shift in the upper air windflow began. The 500-millibar trough
moved from the Arctic Ocean to the southeastern Bering Sea, where it was
centered at the end of the second week in June. In the process of shifting,
the air cooled aloft, resulting in a more unstable atmosphere over Alaska.
Convective showers began to develop over the interior during the first few
days of the second week. By the end of the second week, the upper air low
was centered over the southeastern Bering Sea, and a cool, moist low level
flow of air from the Bering Sea had stabilized the air over western Alaska.
This condition was not favorable for cloud seeding, although it produced
considerable cloudiness with some natural rainfall. During the last week of
June, a 500-millibar ridge from western Canada built westward into Alaska.
This shifted the lower level flow of air to the east and warm air flow into
Alaska from Canada at low altitudes. A more unstable atmosphere resulted,
and convective showers and thunderstorms occurred, making cloud seeding
conditions ideal. During the month, 12 days presented conditions suitable
for weather modification within 200 miles of Galena.
July
At the beginning of the month, a ridge extended from western Canada
westward into Alaska. Moist unstable air covered the State with considerable
shower and thundershower activity in the interior. Conditions favorable for
cloud seeding were excellent throughout interior Alaska. During the middle
of the first week, a 500-millibar trough began to intensify and deepened
southward into the Bering Sea. A south to southwest flow developed over
Alaska bringing cool stable air from the Bering Sea into the interior. The
resulting weather was cloudy and damp over all but the northeast interior of
the State. The stable condition of the atmosphere resulted in poor cloud
seeding conditions. Convective shower and thunderstorm activity continued
over the northeastern interior, however. By the third week of July, the
trough in the Bering Sea moved westward and a ridge from western Canada
built westward into Alaska. An easterly circulation overlay all but the Arctic
coast, where winds were westerly. The circulation caused drying over the
State. Convective shower and thunderstorm activity was confined to the
slopes of the Brooks Range because of the presence of warm air at altitudes
above 15,000 feet in the southern and central portions of Alaska. The
atmosphere became even more stable during the final week of July when the
ridge over Alaska weakened, the trough in the Bering Sea shifted eastward,
and a southerly flow over the State once again developed. The resulting
influx of cool, moist, stable air continued to make cloud seeding unprofit-
able over the entire State. During the month, only 4 days presented condi-
tions suitable for weather modification within the expanded area north of
the Alaska Range and south of the Brooks Range from the Canadian border
to the Bering Sea.
155
-----------------------------------------~--------~---~
ic
" ,
1-
~-
......
VI
0\
Appendix 6
OPERATIONS SUMMARY
Date I Operative area Computer readout Fires flown and No. of Very pistol Results/
latitude-longitude flares used and type remarks
6-10-70 50 mi.-Galena Marginal-Galena Simulated fire One system 3 Rain area spread from
(ground observation) Favorable-McGrath 230° mag 3I nm (2 cells) I slowburn I-to 3-mi. diameter,
Galena (I68 gm. Agl) moved to ENE.
6-II-70 200 mi.-Galena Favorable-Galena Ganes #92IS (1)8 mi. SW (I) 2 Cloud No. I moved
(ground observation-Unfavorable-McGrath (ISO acres) of fire 1 slowburn bver fire with moderate
negative) 63-02N156-30W (2)over fire (108 gm. Agl) rain on fire.
(2) 1 slowburn
(18 gm. Agl)
6-14-70 200 mi.-Galena Favorable-Galena Rennie #9221 One cloud 2 Little effect.
(ground observation) Favorable-McGrath (3 acres) over fire I slowburn Clouds too small in
63-38N 156-59W (I 18 gm. Agl) fire area.
6-16-70 50 mi.-Galena Favorable-Galena Roundabout (I) Over fire (1) 1 Second cloud grew in
(no ground (marginal in p.m.) #9533 ( 40 acres) (2) 7 mi. (I 50 gm. Agl) diameter and light rain
observation) 65-33N 158-33W upwind (2) 1 slowburn observed on or near fire.
(18 gm. Agl)
6-30-70 200 mi.-Galena Favorable-Galena Hog #9571 None None Nearest seedable cloud
(ground observation) (unfavorable to west) (15 acres) 15 miles away.
65-56NIS 5-0 SW
7-2-70 200 mi.-Galena Favorable-Galena Reindeer #9580 None None All seedable clouds 10 miles
(no ground Favorable-McGrath (I7 acres) west of No. 9580.
observation) 65-25N I54-35W None in other areas.
7-2-70 200 mi.-Galena Favorable-Galena Oscars Cabin None None No cumulus
(no ground Favorable-McGrath #9577 (2 acres) clouds in area.
observation) 66-39N152-55W
Old Dummy None None No cumulus
#9576 (20 acres) clouds in area.
66-08N 151-48W
11< !11"'"'··;r-··w..,.,...,1!nT~-~·!19l>"l1 I ,.,.TT. ,~-W~>"7'VIT'•'I'"I J'' 11 '"'"'I I ' .• ~ I Wllf<ll TJWT":.--~ 1 ·~ II !I q 11'<1 :Ill I ill
Vl
.....;)
Date Operative area
7-3-70 50 mi.-Galena
(ground observation)
7-4-70 200 mi.-Galena
(no ground
observation)
7-5-70 200 mi.-Galena
(no ground
observation)
7-7-70 200 mi.-Galena
(no ground
observation)
7-15-70 200 mi.-Galena
(ground observation)
-j!TIC 1 .,,.111
' I
Computer readout
Favorable~Galena
in morning
Unfavorable-Galena
in afternoon
Unfavorable-
Kotzebue
Favorable-Galena
Unfavorable-Galena
Unfavorable-Galena
Favorable-McGrath
Favorable-Galena
Favorable-Kotzebue
(Galena unfavorable
in afternoon)
Appendix 6 (Continued)
OPERATIONS SUMMARY
Fires flown and
latitude-longitude
Nay #9586 ) One system
(80 acres) (2 cells)
65-26N 155-33W 5 mi. SE fire
Knob #9593
No. of Very pistol
flares used and type
2 slowburn
(36 gm. Agl)
(0.1 acres) I All three essentially one fire
Cottonwood
#9594
(0.1 acres)
(Additional reconnaissance of two priority areas:
Holiday Creek #9596 66-23N 155-36W.
Daklia #9601 66-15N 156-18W.
No seedable clouds near fires.)
Daklia #960 1 3 clouds 9
(125 acres) NW of fire 1 slowburn
( 468 gm. Agl)
Star #9615 4 clouds 5
(10 acres) NW of fire (250 gm. Agl)
65-17N 156-39W
Alameda #9646 None None
(1 ,800 acres)
65-06N 161-04W
Kitlik River One SWof 1
#9579 (35 acres) fire 1 slowburn
67-15N 159-48W (68 gm. Agl)
Hunger #9633 One 3
(3,000 acres) (150 gm. Agl)
66-14N 158-SSW
Octopus #9618 None None
(1 ,200 acres)
66-00N 157-25W
Daklia #960 1 None None
(75 acres)
66-15N 156-18W
Results/
remarks
Light to moderate rain, but
not moving toward fire.
Moderate rain on north end of
fire No. 9601
Moderate to heavy rain on fire
changed flames to light smoke
on No. 9615.
Assistance requested at Koyuk
Village. No seedable clouds.
Moderate rain to within
half a mile of fire before
aircraft left scene.
Rain area below cloud spread
eastward over fire.
Clouds unsuitable.
Clouds unsuitable.
", -,.r,p---.,, -1 'l~"'~"r'r "'"T' 11 ''~ • --~'f·c-r>rr;~ ~--, 1 · J "'W' f"·l' l<ltlF~IT~rr"!' 1 ,,-·r. -u rr 1 ·;~!I T1 ·'I 1111'
158
--~----------------
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
Background., practice., and
'
potential of chemicals
in controlling wildfires
Abstract
Chemicals play an increasingly important role in fire control operations.
Techniques have progressed from applications of borate and bentonite
slurries in the 1950's, to the current widespread utilization of long-term
retardants-diammonium phosphate, ammonium sulfate, and ammonium
pyro (poly) phosphate.
It is anticipated that use of fixed-wing aircraft for retardant employment
will expand, supplemented by utilization of ground units and helicopters for
point applications; however, i'n Alaska the limited road net restricts
application other than by fixed-wing aircraft. The potential for significant
environmental damage from use of chemical fire retardants is considered
extremely low.
Chemicals are playing &n ever-increasing role in improving the efficiency
of fire control operations. The objectives of this review are:
1. To sketch a perspective from which we can examine chemicals as
used today and evaluate their potential for further strengthening our
efforts toward controlling wildfires.
2. To arialyze tomorrow's potential application vehicles and the poten-
tial for complementary retardant tailoring.
3. To pinpoint backup problems and progress toward their solution.
4. To discuss problems specific to the Far North, approaches to their
solution and some of the ecological considerations involved.
Today's practice is the result of an evolution of chemicals and aircraft.
During the 1920's, attempts were made to apply water to inaccessible fire-
lines with World War I aircraft. This was essentially abandoned. Experiments
during the 1930's (1) showed that ammonium phosphate solutions had
promise for subduing wildfires. The conclusion from this early work with
chemicals was that they had value only when water was extremely hard to
------------------------~----------
Avrom R. Handleman
Commercial Development
Manager, Wildfire
Monsanto Company,
St. Louis, Missouri
159
f-
1;:-
~-
160
come by. These chemicals were in somewhat limited supply and high in
price, and the rate of activity was slow.
Delivery Vehicles
World War I aircraft
Otters, Beavers, PBY's
TBM's, B-17's, F7F's
B-25's, B-26's, PBY's
Same aircraft
Trend toward larger
aircraft
Changed aircraft
Helicopters
Ground tankers
Sprayers
?
HISTORY
Timing
1920's
1930's
1950's
1960's
1970's
Chemicals
Water
Ammonium phosphates
Water
Borate
Bentonite
Long-term retardants
DAP, MAP, 11/37/0
10/34/0
Thickened phosphates
and sulfates
Tailored long-term
retardants
The effort leading to the present state-of-the-art dates back no more than
about 20 years. During the 1950's, World War II aircraft began to be used in
the Western United States and Alaska to deliver retardant payloads (2), and
Beavers and Otters were used to apply water from lakes in Central Canada
and North-central United States. The first heavily used retardant was borate,
which was discontinued because of its soil sterilizing characteristics. Al-
though borate had some true retardancy (effectiveness after drying), its
primary value was in its ability to plaster a thick layer of water on the fuel.
It was replaced with nontoxic bentonite clay, which was effective only
because of its water-holding and coating ability and was, therefore, classified
as a "short-term" retardant.
The efforts entered a maturing and sophisticating process during the
1960's. Essentially, the same aircraft were used, but toward the end of the
decade a preference for larger aircraft was detectable. The chemicals changed
drastically and assumed the direction they are now taking. True "long-term"
retardants came into their own. Ammonium phosphate solutions appeared in
Georgia, Florida, and North Carolina. Initially, solutions of the dry salts,
diammonium phosphate (DAP) and monoammonium phosphate (MAP),
were used. Then, for ease of mixing, liquid fertilizer solutions (11-37-0 and
1 0-34-0) were substituted since they were readily available there in the rela-
tively (to the West) small quantities used.
When DAP solutions were introduced in California, they were found to
be unsuitable. Not enough chemical could be deposited on the fuel surface
to be effective against the much more severe fire intensities. Also DAP
solutions dropped poorly in windy conditions at the altitudes required for
safety in the more rugged terrain. Furthermore, the question of safety from
corrosion damage to aircraft was faced squarely. These problems were dealt
with by adding thickening agents and corrosion inhibitors. Performance of
DAP and ammonium sulfate-based materials was improved to the extent that
they totally replaced the earlier materials by 1965.
A. How Do Wildfire Retardants Work?
As now used, chemical fire retardants are a mixture of materials to
make them perform in the desired manner. An ammonium salt of
sulfuric, phosphoric, or pyrophosphoric acid shifts pyrolysis in the
preheating stage towards reactions which convert cellulose (fuel) to
carbon and water-absorbing heat and removing fuel. Additives are
used to improve visibility and consistency (viscosity), minimize cor-
rosive damage to susceptible materials which retardants contact, and,
where needed, improve stability and flow. The major functional
components are worthy of review both to point out what can be
expected of presently available materials and to suggest possible
modifications (in physical or chemical properties). These could be
designed into retardants to improve their performance in particular
applications.
FUNCTIONAL COMPONENTS
• Retardant salt
• Thickeners
• Corrosion inhibitors
• Color
• Stabilizer
• Flow conditioner
1. The retardants (salts) themselves.
The commonly used retardant salts are diammonium phosphate
(DAP), ammonium sulfate, and ammonium pyro(poly)phosphate.
Monoammonium phosphate (MAP) has and can be used, but cur-
rent economics rule it out. The first two are available in dry form
and are rapidly dissolved (not slurried as common usage suggests)
at the time of use. The third is used mostly from the liquid
fertilizer (1 0-34-0 or 11-3 7 -0) form although a dry relative
( 12-61-0) is available.
On a weight/ effectiveness basis, the phosphates are reported
to be effective in direct proportion to their phosphorus or
phosphoric anhydride (P 2 0 5 ) content, and ammonium sulfate to
be about half as effective as DAP (3). Since the sulfuric anhydride
(S03 ) content of ammonium sulfate is identical to the P2 0 5
content of DAP, we conclude that a pound of P2 0 5 equals 2
pounds of S03 when uniformly applied to the fuel. The second
number in the liquid fertilizer designations refers to P2 0 5 con-
tent, and a fertilizer description for DAP is 21-5 3.5-0.
161
162
RETARDANT SALTS
Salt
DAP
Ammonium sulfate
11/37/0
Borate
10/34/0
12/61/0
Pounds to
Equal Retardancy
of 1 Pound DAP
1
2
1.6
5.0
1.7
0.9
Both laboratory results and field practice support the above
within our ability to me?sure or compare. The Macon fire Labor-
atory of the U.S. Forest Service reported the first four rankings of
effectiveness. Effectiveness of 1 0-34-0 and 12-61-0 were calcu-
lated from the ratios of their P2 0 5 content to tnat of DAP. The
best field use comparisons are available for DAP vs. ammonium
sulfate. The commercial products PI:IOS-CHEK® 202, fire ~hemi
cal, and Firetrol* 100, fire chemical, at recommended use levels
have been consid~red equivalent for many years on the basjs of
field evaluations. To g~in equivalence with sulfate, the Firetrol
100 uses a combiriation of 50 percent higher salt concentration
than that of DAP in tp_e PHOS-CHEK and employs a clay· thick-
ener to plaster a thicker layer on the surface of the fueJ. This
equivalence illustrates three different approaches toward pbtain-
ing the desired _Rerform~mce in a complete retardant~retardant
concentration, layer thickness on the fuel, and specific effective-
ness of the saJt. i .
2. Consistency (viscosity).
Viscosity control is obtained through the addition of gum or clay
thicke11ers. These ;ue added to control the thickness of the layer
which clings to the fuel and to modify the drop pattern as the
retardant leaves the aircraft. Clay thickeners have the property of
depositing a thicker layer than gums at tne same apparent viscos-
ity, because they don't flow at all under gravity when on the fuel
as a layer. They only exhibit their viscosity when moving or
forced.
Gum thickeners flow more slowly as viscosity increases, but
flow tends to continue as long as there is any driving force (such
as gravity), as with honey. For this reason, the properties of clay-
thickened materials are not directly comparable with those
thickened with gum on a number-for-number basis. In fact, the
same numbers obtained with the same type of standardized
viscometer can have different meanings when different gums are
*Registered trademark of Arizona Agrochemical Company.
-----~--~~---~---~--~-~-------~---------------------·-·-----~~ -----· --------------
involved. For example, if one measures time of passage through a
Marsh Funnel for a CMC (carboxymethylcellulose) thickened
retardant, which indicates I ,000 cps ( centapoise) on a Brookfield
viscometer, he will observe a time of 90 seconds. A Guar-
thickened retardant indicating I ,000 cps on a Brookfield will
show 30 seconds on the Marsh Funnel. This indicates identical
resistance to flow at the higher shear rate of the Brookfield, but a
marked difference when pulled only by gravity.
EFFECT OF THICKENER TYPE
ON APPARENT VISCOSITY
Brookfield Marsh Funnel
Thickener Type CPS Seconds
CMC 1000 90
Guar 1000 30
Clay 1000 27
Discrepancies such as these do not imply that either of the
instruments or either of the retardants are good or bad, but they
illustrate the possibility of comparing apples with oranges in
selecting numbers for specifications or evaluations. Empirical rela-
tionships between air drop and on-the-fire behavior and numbers
obtained on either of the instruments, or indeed other instru-
ments, are quite valid for defining a desired performance for
retardants utilizing a specific thickener-the numbers just can't
cross over. In fact, we may one day be independently controlling
various properties of flow to optimize retardants of greater
sophistication than those we use today, if it is shown that these
properties can independently benefit performance on the fireline.
Ideas on how viscosity control can be used to improve the
effectiveness of retardants applied in different ways are given
below to illustrate their use.
From fixed-wing aircraft, a fairly tight drop pattern can pene-
trate wind and reach the target from higher altitude than can a
diffuse spray. This can be achieved through increasing viscosity,
reducing speed, or modifying the discharge characteristics of the
drop tank (an all too little understood area). For the near term,
we are going to use the hardware we have, and both tank dis-
charge and minimum speed are characteristic of the hardware and
not usually within our control. Viscosity, however, can be modi-
fied rather easily, if a better definition of what is wanted becomes
available. A ceiling is imposed on viscosity increases by the real
possibility of making a retardant so thick that it will not spread
on the surface of the fuel to provide complete coverage at an
economical application rate. Likewise, wind drift and layer thick-
ness requirements impose a floor.
---------~--
163
164
EFFECT OF THICKENERS
Thinness
Wind drift
High drops disperse
Larger area
Easier flow
Shadowing
Thin layer
Thickness
Penetrate wind
High OK_
Slow flow
Thick layer
Wrap around
Smaller pattern
Greater percent of drop on target
As currently used, thickened, long-term retardants have con-
trolled viscosities to provide what appears to be a satisfactory
compromise for the severe problems of southern California.
Further attention is being given to this question as it may apply
to the Far North. It appears that a somewhat thinner material
carrying more retardant salt in a gallon might provide greater
efficiency (treated area per gallon) in the North where high level
drops are seldom necessary and fire intensities are not so great as
to require a thick layer adhering to the fuel. However, such
changes must be made with care; if viscosity is too low, wind-drift
losses will become excessive and nothing will be gained.
From helicopters, both speed and altitude can be controlled,
almost at will, so viscosity desired can be a compromise among
wind drift, spread desired, and layer thickness desired. Good
results have been obtained with viscosities from 100 to 1 ,800 cps.
Even unthickened materials have performed well, but measure-
ments have been made, which showed that a viscosity of 100 cps
or more gave markedly better percentages of drop reaching the
target during wind than did unthickened retardant (4). A problem
here is to adjust drop speed to thicker materials. Good coverage
can be obtained on a larger area by dropping from a somewhat
greater height and/or speed, with some thickening. A higher salt
concentration can utilize this greater spread to give more area
treated per gallon at the same retardant dosage per unit 9f area
than a concentrated drop at lower salt concentration.
With ground tankers, the only benefits from thickening are
greater layer thickness on the fuel, and a longer, tighter trajectory
from a straight stream nozzle. Viscosities of 200 cps or more have
been found to harm spray patterns and to require excessive pres-
sure to drive the material through long and/or small diameter
hoses. An apparently effective range is from no thickening to 1 00
cps, but no data available to the author at this time define it more
closely. Tests planned for summer 1971 should yield data upon
which sound selections can be based.
3. Corrosion.
Without inhibitors, the phosphates and sulfate used in retardants
are corrosive to aluminum and copper and their alloys, as well as
to zinc. Ammonium sulfate is quite damaging to iron, and some
damage to iron by pyrophosphate has been noted. Both the
sulfate and the pyrophosphate are extremely damaging to
magnesium. DAP has caused little or no damage to iron; and
although it has been reported to attack magnesium, the author
and his associates have been unable to observe or cause such
damage.
CORROSION CONTROL
Commercial
Retardant Type Action on
Aluminum Copper, etc. Magnesium Steel Zinc
DAP type N N N N s
Sulfate type N s s p s
10/34/0
or SL s s ? s
11/37/0
N = Negligible SL = Slight P = Slow S = Severe
Commercially available DAP and sulfate-based retardants ap-
pear to be well inhibited against corrosive attack on aluminum,
and a moderate degree of protection has been achieved with pyro-
phosphate (liquid)-based retardants. Thus far, only the DAP-based
retardants are satisfactorily inhibited against attack on copper and
its alloys.
The significance of corrosivity is hard to define in an overall
sense, but certain points are clear from analysis. Damage to
aluminum and its copper alloys could pose both safety and
equipment-life _problems in aircraft. Information on this as a
result of retardant action is not readily available, but it needs to
be gathered and reported. In the case of airbase facilities, dif-
ferences are observed, and experience has varied from almost no
damage to almost complete inactivation of facilities. Inhibited
sulfate-based retardants have damaged or destroyed tanks, mani-
folds, and valves at several installations, but damage from inhib-
ited DAP-based materials has been negligible. Reports on the
ef~ects of 1 0-34-0 types are not generally available.
If retardants are to be employed in existing ground tankers,
they must not cause more than minimal damage to copper alloys
and steel. This limits the practical choice to properly inhibited
DAP types unless good inhibitors are developed for sulfate-or
pyrophosphate-based products or unless high maintenance and
replacement costs are acceptable.
~-
165
166
B. Application Vehicles.
1. Fixed-Wing Aircraft,
A discussion of the virtues and shortcomings of types of aircraft is
a study in itself and involves a great deal of opinion. Nevertheless,
several observations seem pertinent.
The author believes fixed-wing aircraft carrying a retardant
payload are here to stay, at least for the early phases of attack
because "they get there firstest with the mostest." There is a
noticeable trend toward aircraft which carry more and fly faster,
in spite of the fact that reduced speed and altitude are required
during effective bombing runs. The small TBM's, B-25's, and
F7F's are phasing out. B-17's are being lovingly preserved because
of their large payload, safety, and fairly good maneuverability.
And PB4Y's and P2V's are in growing demand. Many expect
C-119's and C-130's to appear on the scene. Hopefully, a general
understanding of tank and discharge design will be developed
soon. Much more could be said here, but the author is better
equipped to tailor chemicals than to select and modify aircraft.
2. Helicopters.
Limited and experimental use of helicopters as direct attack
vehicles has grown slowly since the 1950's. Even today their
unique value lies in their ability to provide the most effective and
rapid manpower and logistical support for firefighting efforts
especially where surface access is difficult or impossible.
Although much of their appeal lies in their multipurpose capa-
\ bility, when they are converted for water or retardant bombing,
they offer unique capabilities-complementing rather than dis-
placing fixed-wing aircraft. Their maneuverability permits precise
attack on portions of the fireline not easily reached by fixed-wing
craft having to cope with terrain problems. Their ability to
operate from bases near the fire permits them (at least the larger
craft) to deliver more retardant (or as is usually the case today,
water) per hour than can fixed-wing craft based any great distance
from the fire. Although types are not discussed here, "the larger
the better" is generally true for retardant application. Their use in
the bombing role is increasing almost as fast as budgets permit.
C. Ground Tankers.
The evolution of ground tankers predates the scope of this review,
but an examination of past efforts and the current status of their use
as vehicles for delivery and application of retardant chemicals is in
order.
Following successful use in aircraft, borate slurries were tried in
ground tankers. Damage to hardware, difficulties in moving the thick
slurries through hoses and nozzles, and support problems eliminated
this approach quickly. Algin-gel and CMC thickeners were tried. These
permitted retaining thick layers of water on the fuel and they could be
handled through conventional pumps, hoses, and nozzles with some
difficulty. Again, support (mixing and supply) proved to be a prob-
lem, and although a significant improvement over plain water's effec-
tiveness was achieved, lasting power was absent. Results were not
considered sufficiently promising to justify the added difficulty.
The next attempt utilized a slightly thickened ammonium phos-
phate solution in 1964 and 1965. Support difficulties coupled with
memories of past frustrations doomed early attempts with this
approach, even though the material was inhibited to prevent damage
to hardware and was of sufficiently thin consistency to handle well in
most conventional ground tankers, hoses, pumps, and nozzles. Where
used-Bureau of Land Management, Idaho; Bureau oflndian Affairs,
Washington; U.S. Forest Service, Montana; and California Division of
Forestry, California-results showed a marked increase in efficiency
over water, but the difficulty of it all proved to be too much.
By taking advantage of retardants' greater effectiveness, the goal
was, and is, to make a 200-gallon slip-on into the equivalent of a 500-
to 1 ,000-gallon unit loaded with water. Between capital squeezes and
the cost of bringing water to the units or the units to water, there still
appears to be strong justification for further pursuit of this approach.
Efforts are being directed toward minimizing past difficulties.
D. What Might Chemicals Do?
Chemicals should be able to increase markedly the effectiveness of
men and hardware. What hardware? What chemicals? How? What is
missing?
The appeal of chemical retardants lies in the fact that the work of
putting 1 gallon on the fuel replaces the work of putting several
gallons of water on it and sometimes can replace the work of building
handlines. Airplanes, helicopters, and ground tankers have been
mentioned as final delivery vehicles. For making or reinforcing line
(when fuel type and terrain permit), agricultural sprayers moving at 3
to 5 or more miles per hour deserve more consideration than they
appear to have received.
It is highly probable that the nitrogen/phosphorus compounds we
use today offer the best "active" components for the retardants of
tomorrow because of their excellent (compared with other known
retardant chemistries) balance of effectiveness, weight, safety, and
cost. It is equally probable that much better formulations can be
tailored for the type of application vehicles to be used. Before these
better formulations can be developed, more information on the re-
quirements of the application equipment must be known. Starts
-----~--~-------·---------------~------------~-------·------~-----·---
L e
167
168
toward generating this information have been made. More studies will
be made this summer and, hopefully, they will continue in the sum-
mers to follow.
But, do these lacks prevent more use of the very good materials
we have today? I don't think so.
The widespread use of chemicals today is from permanent fixed-
wing airbases, where support and supply are available. To be applied
advantageously from helicopters and ground equipment, chemical
payloads musLbe available to application equipment near the fire.
Only recently have really promising efforts been begun to make this
support less trouble than it is worth. To be so, the chemicals must be
transported to the fire scene in as concentrated a form as possible,
they must be mixed at high speed, and the support effort must re-
move a minimum of manpower from the fireline.
Two approaches are being taken today. Liquid retardant concen-
trates are the preferred approach by some, because of the simplicity
of mixing and handling. Others are working with dry concentrates to
avoid hauling water to water, and to take advantage of the much
better corrosion protection and storage ease and stability. Both types
depend upon ammonium phosphates as the active retardant. It ap-
pears that both types will be available in manageably sized bulk
containers from which automatic, continuous mixing will be possible.
An example of a completely automatic dry support unit carrying
enough powder to make over 30,000 gallons is shown. (See photo.)
This is fine where there is a road system near the available water, but
small air portable units are required to support helicopters where
roads are scarce. These are scheduled for tests in Alaska during the
1971 fire season.
The justification for using retardants is that each load can be the
equivalent of several loads of water. The cost of application is essen-
tially the same. The total manpower involved is only slightly greater
than that required to apply a similar quantity of water. If there is
indeed a severalfold increase in effectiveness per load, then we can
achieve a very real increase in effectiveness of manpower and equip-
ment. Operational tests should be carried out to gain more precise
answers to these "ifs."
Another opportunity for using portable support (developed for
helicopters and ground tankers) lies with the original chemical carrier,
the airplane. Really portable facilities would permit establishment of
temporary operations at unimproved airstrips (with water nearby)
closer to the fire. Even if retardant is delivered by air, it is more
efficient to fly 1.07 pounds of dry retardant than 8.9 pounds of
mixed retardant. Thus, one cargo plane could be supporting one or
more air tankers, which could deliver much more to the fire each
hour than if they were returning to a more distant, permanent base.
With this potential, new tactics can be developed; but personnel
must be trained to execute them to realize anticipated results. Hope-
fully, future ventures will define some of the tactical possibilities and
problems and point up changes which will ultimately be required in
training programs.
E. The Far North.
Some of the characteristics which distinguish the fire problems of the
North from those of the more southern States are distances, fuels,
lack of roads, longer time required for initial attack, short (if any)
nights, and more distance. The new developments aimed at porta-
bility eventually should contribute some relief to the distance prob-
lem and, coupled with air transport, to the problem of lack of roads.
The longer time before initial attack increases the need for support
bombing, and improved capability for close-in bases for the bombers
multiplies their utility.
Some Arctic fuel situations are similar to those encountered in
the north-central United States and are handled well with the same
approaches as are used in the South, but the tundra is something else.
If we could coat the moss down to permafrost, we could probably
stop a tundra fire with retardant. But we can't today. Some sur-
factants and wetting agents have been tried without any (to the
author's knowledge) significant success. More work is justified in this
area, and partial success may be possible. However, I know of no
universal chemical approach to tundra fires at this time.
Implications for the ecology are twofold. What is the effect of
fire? What is the effect of the retardants? They are both broad sub-
jects, especially that of fire, and comments here will be limited to the
retardants. U.S. Forest Service and Bureau of Land Management are
conducting a definitive study of the subject (5), but experience and
published literature already shed considerable light.
The author and others with whom he has discussed the subject see
little effect on land except a localized fertilizing action. What hap-
pens in water when the retardants are inadvertently applied to a
stream or lake deserves closer examination. It is difficult to imagine
how the relatively small quantities used can cause a serious eutrophi-
cation problem from the noncontinuous introduction, characteristic
of fire control actions. The questions that must be answered seem to
pertain to acute toxicity at or close to the time the retardants are
introduced into wild water. DAP-based retardants were found to have
a 48-hour TLM of 46 p.p.m. (parts per million) for rainbow trout and
25 p.p.m. for bluegills in one study (6).
The literature shows ammonia to be harmful at concentrations of
from 5-15 p.p.m. (7, 8, 9) and safe under 2.0 p.p.m. for exposures
--~---~~------------· ---·---------------·-------
169
----------~-----
170
under 96 hours. The DAP-based retardants contain about 21 percent
ammonia, so the observed bluegill toxicity of 25 p.p.m. involved an
ammonia concentration of slightly over 5 p.p.m. and the trout
toxicity of 46 p.p.m. involved an ammonia concentration of about
9.7 p.p.m. Both of these are within the reported dangerous range for
ammonia, and it appears that ammonia can account for the toxic
contribution of the retardant . This is a fairly high concentration, and
it is difficult to see how it could be reached on any broad scale with
retardants-especially since they are not usually introduced into
water except in the small quantities required to tie a fireline to a
stream or lake. Very localized kills could be caused in small streams ,
and very small impoundments of standing water could be harmed. It
is hard to visualize any broad ecological impact from retardants.
In summary , the path has been traced to present practice in the use of
retardants to fight wildfire. The characteristics of the components of com-
plete retardants have been discussed. Ways in which retardant use could be
expanded beneficially have been explored . Needs and trends were analyzed.
The problem of tundra was found to be still with us. And it was suggested
that the potential for significant ecological damage from the use of retar-
dants was extremely unlikely.
Literature Cited
1. Traux, T. R. 1939. Fire Contr. Notes 3(1). (Also in J. Forest. 37: 677.)
2. "Operation Firestop," Progr. Rep. No. 4: Fire Retardants. Pac. South-
west Forest & Range Exp. Sta., Berkeley, Calif. 12 p. 1955.
3. Johanson, R. W. 1965. Progr. Rep. No. 2102 (S5). Southeast. Forest
Fire Lab., Macon, Ga.
4. Morgenthaler, W. W. PHOS-CHEK® DAP for fire control-its use from
helicopters, Progr. Rep. 3-00-760.01-6512 (Confidential), June 25,
1969. Monsanto Co., Inorganic Chern. Div., St. Louis, Mo.
5. Borovicka, R., E. Palmer, and C. George. Meeting notes and literature
review on plans for interagency study of the relationship of fire retar-
dants and the environment. Portland, Oreg., Dec. 7-8, 1970, and private
communications.
6. Rep. No. BTL 70-9 to Monsanto Co., June 18, 1970. Ind. Biotest Lab.,
Inc., 1810 Frontage Rd., Northbrook, Ill. 60062.
7. "Appraisal of Chemical Waste Problems by Fish Toxicity Tests," Sewage
& Ind. Wastes 24: 1397-1401 (Nov. 1952).
8. Turnbull, H., J. G. DeMann, and R. F. Weston. 1954. Toxicity of vari-
ous refinery material to fresh water fish. Ind. & Eng. Chern. 46(2).
9. Cairns, J., Jr., and A. Scheier. The relationship bluegill sunfish body size
to tolerance for some common chemicals. Dep .. Limnol., Acad. Natur.
Sci. Philadelphia. Journal reference not shown, but references are cited
through 1957.
10. U.S. Geological Survey, provisional data received in communication
from Bureau of Land Management, May 1970.
11. Tarzwell, C. M. 1957. Water quality criteria for aquatic life. U.S. Dep.
Health, Educ. & Welfare.
12. Lyons, J. W. 1970. The chemistry and uses of fire retardants. New
York: Wiley-Interscience.
171
172
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Values protected
• • • In Interior
Alaska
Abstract
The Bureau of Land Management in Alaska allocates fire control re-
sources during critical situations according to a plan that considers resource
values, fire danger, and numbers of men committed to fires. Values were
assigned by resource managers according to a standard point value system.
Justification of fire expenditures must consider values saved. Graphs are
attached which illustrate the relationship of costs, losses, and values saved at
varying levels of input.
We are often asked, "Why do you fight fires in Alaska, particularly when
the costs are so high?" There is also an implied portion of the question, "and
when the values are so low." This is essentially a question for the land manager
rather than the fire control specialist for it is he who must decide how much
protection he needs and can afford. Over the years, land managers have
developed policies and procedures to guide fire control efforts in Alaska. In
answering the question I will outline the Bureau of Land Management's (BLM)
fire control policies, priority system, and fund allocation rationale. I will also
touch on how the present state of knowledge affects our decisionmaking,
and how future knowledge will be integrated into our program.
Policies
First of all, let me explain that most of the wildfires BLM fights in Alaska
occur on lands administered by agencies other than BLM. Therefore, we take
action on these fires at the direction of the managing agencies. Sixty-nine
percent of the wildfires BLM fought in 1969 and 1970 occurred on State
and private lands covered by a reimbursable contract. Over 95 percent of
these fires were man-caused and occurred primarily on high value lands near
population centers. BLM also took action on fires on lands of Bureau of
Sport Fisheries and Wildlife, Bureau of Indian Affairs, and National Park
Service under cooperative agreements. Each of these land management
agencies has its own objectives, and BLM is serving as the Department of
Interior's fire department in these instances. On the public lands, which
J. H. Richardson
Bureau of
Land Management
Anchorage, Alaska
173
174
-· -----~-~-·---~-----·· --·------------------------~ ··-----~-~------~ --
comprise about 85 percent of the 220 million fire-prone acres of interior
Alaska, however, BLM is the managing agency as well as the protection
agency. Our policies concerning fires fought on these lands are:
US. Department of the Interior. -"Hold fire losses to the minimum pos-
sible consistent with the least expenditure of public funds necessary to pro-
vide adequate protection of the resources in the public interest." One way of
expressing this policy as a formula is: Costs plus losses= minimum.
Bureau of Land Management.-"!. Control all fires burning in the higher-
value areas.
2. Control all fires burning in the lower-value areas when possible and
when the fire potential on higher-value areas is low enough to allow
risking BLM capabilities."
Priority System
To implement these policies, we have a priority system or action plan by
which we allocate men and resources to going fires and to readiness reserves.
Since we don't have the capability to fight all fires during severe years, we
use three determinants to ration our forces: resource values, fire-danger rat-
ing, and number of men committed to fires. During periods of low fire
activity, we take action on all fires. When weather is critical and we already
have large numbers of men on fires, we hold back a reserve to take action on
fires in the highest value areas. Th~se areas are along the highways and near
villages. In years like 1968 and 1969, sheer numbers of fires overwhelmed us
and we had to let some of the fires in the lower value areas go. With 4,000
men deployed on the 1969 Swanson River fire near Kenai, we had only very
limited initial attack reserves available for new fires. As a result of this
system, one group of fires north of Tanana in 1969 burned together to form
a complex of 1 million acres. Another fire burned during the period of May
through October from Chalkyitsik to Fort Yukon, a distance of 44 miles.
Fires in 1969 produced an estimated 145,000 cubic miles of smoke which
persisted from mid-June through mid-July.
These experiences have shown us that large, uncontrolled wildfires even-
tually become a threat to life, property, or military installations. Regardless
of what is burning, the smoke that drifts from them covers high-value areas
and stops aerial detection and air attack on new fires. We have not been able
to identify any area where fires can safely be left to burn without serious
consequences and high costs.
The only effective means of control we have is to take all-out action on
these fires while they are small and controllable. Wildfire is not a precision
tool that can be allowed to burn to certain predetermined limits, then stopped.
It is not like a gas stove that can be turned up, then turned down when the
pot starts to boil. It is more like an atomic reaction that we either stop at the
beginning or don't stop at all. Prescribed fire, on the other hand, can be a
highly useful management tool when used within proper limits.
Of interest here is the resource value determinant of the action plan. This
is a component of the Bureau's Normal Fire Year Planning System. Areas of
similar value are delineated on a map encompassing all ownerships in the
protection area. Value components are then rated by resource managers with a
standard point system. Areas with the highest point total receive the highest
relative ratings. Elements considered are soil, watersheds, timber, recreation,
wildlife habitat, grazing, and potential for development. The weaknesses in
this rating system are the lack of resource inventories in most of Alaska and
the lack of knowledge of the effect of wildfires on certain compone11ts such
as soil, watersheds, and fisheries.
Fund Allocation Rationale
Although our action plan guides and helps us to implement suppression
policy, it is more difficult to quantify guides to action in tlle least-cost-plus-
damage policy. Therefore, we have prepared cost-benefit graphs to illustrate
the relationship of fire control cost to values protected. Further discussion
of the concept is found in K. P. Davis (p. 484-487). 1
The graphs were based on a formula derived from the basic policy ex-
pressed as follows:
1. Cost plus loss = Minimum
2 · Cost plus loss -Cos· t/benefit rat1·o
V 1 d -a ues save
or
3. CplusL =R NminusL
where:
R = Ratio of costs to benefits. A value less than 1.0 is beneficial. 1.0 is
the break-even point.
C =Average annual protection costs including both presuppression and
suppression ($).
L = Average annual loss ($). In this analysis, it is derived from esti-
mated average acreage losses at various sustained funding levels
times an estimated average loss figure per acre.
N =Average annual loss ($) if no fire control action were taken. De-
rived from estimated no-control burned acreage times an estimated
average loss figure per acre.
In order to prepare these graphs, basic assumptions and estimates concern-
ing the three dependent variables considered had to be made:
1 Kenneth P. Davis. Forest fire: control and use. McGraw-Hill Book Co., Inc., New York. 1959.
175
--------------------------------
176
1. Values saved
There are values to protect. If there are none, then no protection is
justified. The emphasis on values saved must be equal to the emphasis
orr costs and losses. In order to calculate values saved, an estimate must
be made of burned acreage if there were no fire protection. We estimate
this would be two to four times the current average annual burn of
800,000 acres in Alaska.
2. Value per acre
The estimated per-acre values of burnable resources must be expressed
in dollars in order to make comparisons, since fire costs are readily
quantifiable in these terms. For interior Alaska this requires estimates
of discounted future values of items such as timber, estimates of offsite
damages such as air and water pollution, and estimates of intangible
values such as loss of scenic beauty or critical wildlife habitat. Since
comparable market transactions are scarce or lacking for much of the
interior, alternative dollar level estimates must be used for break-even
comparisons.
Estimates must be made of the degree of loss due to wildfire. For
example, not all the merchantable timber in a commercial stand is
necessarily destroyed by a wildfire. There may be salvage value in the
stand for a time after the fire. Similarly, the base ~and and mineral
values are not lost, only the burnable surface resources.
3. Protection effectiveness
The effect of varying cost levels of protection must be estimated. The
current average cost and loss level is known. Loss levels with zero
protection and with very high intensive protection can be made fairly
readily. This gives three points on the curve. Precise estimates of the
intermediate levels of protection are more difficult to plot on the curve.
Statistical averages of costs and losses covering a minimum of 1 0 to 20
years must be used since the effect of weather in any given year is so
variable~
Charts 1 to 4 using the above criteria illustrate the following points:
1. With no protection, there are measurable costs to the landowner or the
public that depend on the estimate one places on average burnable
resource value. For example, chart 2 shows that with no protection,
there is a $5.5 million loss at the $2 per acre level.
2. With too much protection, costs exceed benefits as shown in chart 2.
3. D~pending on one's estimate of values, optimum levels of protection
can be determined. For the assumptions used, chart 3 shows the
optimum level of protection cost to be about $7 million.
----------------------------
:? :§.
~ 2
a
"' .
~ <
1 <
f < I
Chart 1 Presuppression and Suppr~ssion Protection Cost ($MM)
15 20
Chart 3 Total Protection Cost ( $ MM)
20
:? :>!
<e
! 15
~
1ii
8
1 10
~
(!;
Chart 2
0
"
20
::; 10
i!
~
Chart 4
Total Protection Cost ( $ MM)
Total Protection Cost ($ MM)
Chart 1.-Estimated acres burned at varying Protection Cost Levels on the Bureau of Land
Management protection area in Alaska. The curves illustrate examples of three
estimates of acreage loss with no protection (2x, 3x, 4x). Illustrated 8J.so are two
estimated levels of acreage loss at the $5 million to $15 million cost levels.
Chart 2.-Cost-Benefit Analysis at $2/acre Resource Value. Since the curves do not inter-
sect, the chart illustrates that costs exceed benefits at an assumed average per
acre value of $2/acre for burnable resources and all on-site, off-site, intangible,
and future values.
Chart 3.-Cost-Benefit Analysis at $4/acre Resource Value. The curves intersect and indi-
cate positive benefits from approximately the $4 million cost level to the $12
million level.
Chart 4.-Cost-Benefit Analysis at $6/acre Resource Value. The large zone of positive
benefits between the curves illustrates the effect of higher estimates of per acre
value.
r-
177
178
By comparing charts 2, 3, and 4, one can see that the average value of
resources saved has a very large influence on the amount of protection cost
that can be justified. Admittedly the values used in constructing the graphs
are based on a wide range of variables and intangibles. However, the process
of constructing the graphs forces one to quantify his particular estimate of
the dependent variables.
Summary
In summary, we have discussed why we fight fires in Alaska. The basic
answer is that we estimate that the values of resources protected are great
enough to justify protection costs. This estimate is based on a number of
factors that require more research and study:
1. Effects of fires-positive as well as negative.
2. Inventories of resources.
3. Better estimates of resource component values based on detailed
economic analyses.
In the meantime, our approach is to provide a level of protection that will
limit damage to the burnable resources and thus preserve the options of
future land managers and decisionmakers.
~-~------~~~-~--""~--~~---~-------------------------
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
White spruce stringers
in a fire-patterned landscape
in interior Alaska1
Abstract
In a south-facing subbasin of Caribou-Poker Creek Research Watershed
near Fairbanks, several mature white spruce stringers, apparent relics of
extensive stands that have escaped fires, were studied.
Tree-ring investigations show that the mature spruce stringers have re-
mained fire-free for at least 200 years, whereas the adjacent areas show
evidence of burning every 40 to 60 years. The tree patterns, composition,
and density of the spruce stringers are quite homogeneous, but those of the
adjacent areas of young birch-spruce show large variations both within the
same area and among different areas. The previously burned areas indicate a
long-term cycling effect (40 to 60 years) which seems to maintain or perpet-
uate a birch-spruce community. The stringers are associated with a slight
depression in microrelief Soil temperature at the l-inch depth showed the
previously burned site was a maximum of t> F. warmer than the stringer site
during summer 19 70. Although the summer of 19 70 was exceedingly wet
and overcast, moisture conditions on the forest floor of the stringers were
much higher than in the adjacent areas. As determined by Colman blocks,
the soil moisture percent by volume of the surface horizon in the stringer
site averaged 61.5 percent for summer 19 70; the previously burned area
averaged 40.2 percent during the same period. The higher soil moisture
content of the stringers, along with possible shielding of these protected
areas from winds during fire conditions, would seem to be significant factors
in keeping the spruce stringers fire-free.
Much of the forested landscape of interior Alaska is a mosaic of tree
species owing to the great number of forest fires which have swept through
the area in the past. Low precipitation, long hours of sunlight in the summer,
highly flammable ground cover, trees which provide good fuel, and frequent
lightning storms combine to make a high fire hazard (5). This condition is
augmented on the south slopes which receive more solar radiation and are
1Parts of the data used in this study were supported by the National Weather Service (ESSA
E 248-69-N) and the Corps of Engineers (DACS 85-70-C-0016).
William A. Quirk and
Dwane J. Sykes
Department of Land
Resources and
Agricultural Sciences,
University of Alaska,
Fairbanks, Alaska
179
180
CAR IBOU-POKER CREEKS RESEARCH WATERSHED
To none River Basin. Alaska
Figure 1.-Map of the study area . See square in subbasin C-2 .
Figure 2.-0verview of mature spruce stringer pattern. View is north, subbasin C-2 .
therefore warmer and drier. The patterned landscape on south-facing slopes
may be intensified by the relative ease with which birch and aspen seed can
be disseminated by the wind. Furthermore, these seeds appear to germinate
more successfully than conifers on areas which are open to the drying
agencies of wind and sun ( 4).
Several mature white spruce stringers were studied with the adjacent
burned areas on a south-facing slope in the Caribou-Poker Creeks Research
Watershed 30 miles north of Fairbanks ( 7) (fig. 1 ). The geology of the area is
chiefly Precambrian schist and gneiss of Birch Creek schist formation (8).
The rocky and poorly developed surface soils are usually silt loams which
have formed in loess parent material. Patterns of the stringers were delin-
eated, and composition and density were determined for burned and un-
burned areas. The two previous severe fires in the burned areas were dated,
and a study was made to pursue possible reasons for the mature spruce
stringers remaining fire-free.
Sites and Methods
The stringer pattern occupied the midsection of a 1 ,200-foot south slope
(figs. 2 and 3). Six mature spruce stringers and the adjacent previously
burned areas were investigated using a line transect at 2,1 00-foot elevation.
At the 2,1 00-foot contour, the mature stringers appeared as definite string-
ers, and all were separated by burned areas (see fig. 4). Further downslope,
some of the stringers coalesced into one connected patch of trees.
~ ~
N
~ "~'1-----+---~~---+----~----+-----~--~~--~----
~
Figure 3.-Mature white spruce tree pattern in the study area.
181
182
A ground reconnaissance of the area was made. Distances were paced off
and maps were drawn to scale. An increment borer was used to take cores
from which growing trees were dated. The cores were stored in plastic straws
which were sealed tightly in the field by heating with a match and pressing
each end together. The cores were wet and the rings counted. In only a very
few instances were the rings so close together as to cause difficulty in count-
ing. The number of rings counted in a core was assumed to be the age of the
tree. To determine the age of fire-killed spruce, the trees were cross-
sectioned with a saw and the rings counted.
-Tree density was obtained-by counting all the trees within a randomly
chosen 120-by 120-foot (l/3-acre) plot. For the burned communities,
names of the species are denoted in order of dominance, on the basis of both
height (community dominance) and density (abundance dominance).
A study site representing the mature spruce was located in stringer 1 and a
site representing the burned areas in burned area l. Vegetation and soil
profile descriptions and soil moisture and temperature determinations were
taken at the two sites. The Troxler surface neutron meter was used through-
out the summer to monitor the moisture content in the upper 6 to 12 inches
of soil. Colman block units were used to measure soil temperature and also
the soil moisture within the various soil horizons. The Colman blocks were cali-
brated in the laboratory by soil weight and volume using undisturbed soil
cores from the field. The volume-based data are used for comparison with
the neutron meter determinations.
N
Scale 1-=":...=-i
Figure 4.-Schematic diagram at the 2,100-foot contour depicting the six stringer com-
munities and the adjacent burned areas.
Results and Discussion
The tree patterns of the mature white spruce stringers are shown in figure
3. The composition and density of the understory (table 1) were uniform
among stringers and observed to be uniform within stringers. The spatial
arrangement and the age of the dominant spruce and birch trees were also
observed to be rather uniform both within and among stringers However,
the density of the spruce varied between 370 and 121 trees per acre. Table 2
presents the d.b.h. of all spruce trees in a random plot sample_ from stringer
1. Trees of all sizes are represented which indicate good regeneration of the
spruce forest. Forty-four percent of the spruce trees had d.b.h. greater than
10 inches and 77 percent had d.b.h. greater than 6 inches. One or two
periods of struggle and release were observed from most of the large spruce
cores (2).
The composition, density, and age of the trees among burned areas were
relatively heterogeneous. Burned area 5 is a spruce community with a den-
sity of 658 spruce, 88 aspen, and 82 birch per acre with scattered willow and
alder (table 1). Burned area 4 is a birch-spruce-alder community with 725
spruce, 685 birch, and 403 alder per acre with scattered aspen and willow.
The composition and density were also highly variable within the same
general area. Several age groups from seedlings to 35 years were found for
white spruce in the burned areas (table 3). On the other hand, dominant
birch in each burned area was 30 to 38 years old. Another similar trend is
that those 30-to 38-year-old birch are the oldest living trees in each of the
burned areas, and spruce has seeded-in at various times later. This is con-
sistent with other findings ( 4).
From the above information, it seems reasonable to conclude that the last
severe fire in the Caribou Creek area was approximately 40 years ago, about
1930. Man's activity from mining and trapping began in the early part of the
20th century. In 1907, C. C. Covert (3) began streamflow measurements
near the mouth of Caribou Creek. There was little activity in the Fairbanks
district prior to the gold discovery of 1902.
A few widely scattered fire-killed spruce remained standing in the burned
areas. Table 4 shows that the oldest fire-killed spruce was 65 years old when
destroyed by the last severe fire in approximately 1930. This would likely
indicate that the severe fire previous to 1930 may have been 65 years earlier,
or approximately 1865. This latter date would be previous to white man's
activity in the basin.
In the spruce stringers, however, the average age of mature spruce trees
was 193 years, and the oldest tree sampled was 208 years (table 1 ). This
indicates that no severe fire has invaded the stringers within the past
200-plus years. Although old living trees were not cut down to look for fire
scars, no other evidence can be found that even moderate fires had pene-
trated these stringers in the past. A few old logs in a rotted state are evident
on the forest floor.
~--
~-
'
183
.....
00
..j:::.
TABLE 1.-The density and age of dominant trees in the spruce stringers and burned areas
Area Community
Density (trees per acre) Age of dominant
Spruce I Birch I Aspen I Willo~ Alder , trees (years)
Stringer 1 Spruce 128 10 -ct) CZ) 185
Stringer 2 Spruce 225 16 -ct) CZ) 194
Stringer 3 Spruce 370 8 ct) CZ) 1603
Stringer 4 Spruce 121 20 -ct) CZ) 208
Stringer 5 Spruce 190 3 -ct) (2) 2203
Stringer 6 Spruce 168 8 -(1) (2) 1903
Average 201 11 ---193
Burned area 1 Birch-spruce 788 2 384 96 ctJ 134 38
Burned area 2 Birch-spruce 523 285 ct) ct) 142 35
Burned area 3 Birch-alder 580 2 226 ct) ct) 258 323
Burned area 4 Birch-spruce-alder 725 685 ct) ct) 403 32
Burned area 5 Spruce 658 82 88 e) (1) 35 3
Burned area 6 Birch-spruce 1,096 161 ct) ct) (I) 303
Average 728 320 ---34
1 Scattered.
2 Understory.
3 Estimated from tree diameters.
-,,,.,. . ....,,0',.,.""""''1"...,..,,'n·-r, ., ·">!" ·~~,.,.,.-·o•-,-,-".
-----------------------·--·-
TABLE 2.-Diameter breast height of all 48 spruce trees located in a random
150-by 1 05-foot plot in stringer 1 (ascending order)
Tree D.b.h. Tree D.b.h. Tree D.b.h. number number number
- --Inches - - -- --Inches - - -- --Inches - -
1 Seedling 17 ·-7 33 11-1/2
2 Seedling 18 8 34 12
3 1 19 8 35 12
4 1 20 8 36 12
5 2 21 8 37 13
6 3 22 8 38 13
7 3-1/2 23 9 39 13
8 3-1/2 24 9 40 13
9 5 25 9 41 14
10 5-1/2 26 9 42 14
11 6 27 10 43 14
12 6 28 10 44 15
13 6 29 10 45 15
14 6 30 10 46 16
15 6-1/2 31 10 47 18
16 7 32 11 48 18
Lutz (5), in his classical study of the ecological effects of fires in Alaska,
states that the isolated stands of a few acres of white spruce (the upland
stringers) and even scattered spruce trees are relicts of extensive stands that
have been destroyed by fire. Scattered mature trees were found outside the
study area to the west. No evidence can be found in the burned areas to
indicate that these areas were or were not once extensive stands of mature
white spruce. How long these areas have been occupied by young communi-
ties of birch or birch and young white spruce is unknown, but it is presumed
to be a long time.
The burned sites were evidently birch-white spruce communities when
they last burned some 40 years ago. Aspen evidently is not a strong competi-
tor with birch on this particular site. The succession seems to be a reoccur-
ring cycle, as a severe fire every 40 to 60 years would appear to perpetuate a
new birch-spruce subclimax community. After a fire, birch comes in first,
then spruce gradually seed-in over a period of 20 to 30 years (table 3). At 40
to 60 years, before the spruce begin to compete with the birch for domi-
nance, a severe fire occurs and starts the cycle over again. Maisurow ( 6)
discussed the cycle where succession is continually being set back by the
reoccurrence of fire.
-~---------------~----------------------
~
~
~
185
,_.
00
0\
TABLE 3.-Forest communities and age of dominant birch and spruce in the burned areas
Burned area
1 . Birch-spruce
2. Birch-spruce
3. Birch-alder
4. Birch-spruce-alder
5. Spruce
6. Birch-spruce
Average
1 Estimated from tree diameters.
2 Seedlings.
1 ol!Hf>•I'Trr"l''' '' ,-,1''11'
Birch
Age of
dominant trees
l Spruce
--------------Years --------------
38 30-35 1
35 1 33
32 1 e)
32 15-20
35 1 20-25
301 20-25
34 20
.,, •• "'"111l'•
Comments
Birch established first; gradual entry of spruce.
Birch established first; gradual_ entry of spruce.
Birch is dominant; spruce understory.
Birch is dominant; gradual entry of spruce.
Scattered birch established first; ~pruce came in gradually.
Scattered birch established first; spruce came in gradually.
•i
TABLE 4.-Age of fire-killed spruce trees which were still standing in 1970
in the burned areas
Tree number
1
2
3
4
5
6
7
8
Age of dead tree
65
57
53
52
48
47
34
28
Comments
These trees were apparently killed
in the last severe fire which was
about 40 years ago. The oldest
trees had been growing for 65-70
years at the time of that fire.
An interesting question concerning the isolated spruce stringers is how
they have managed to remain relatively fire-free in an overall fire-prone
landscape. They appear totally unaffected by the many fires which have
presumably burned in this area in the past. In attempts to study this prob-
lem, papers (1, 5) mentioned the presence of upland stringers in a fire
landscape. However, no reasons were offered as possible explanations for
their existence in a fire-dominated landscape. These stringers are found not
only in the study area but have been reported common to all of the Alaska
interior, especially on south-facing slopes (5).
The minute topographic features of all the stringers appear to be signifi-
cantly different from those of the burned areas. The stringers are in very
minor depressions or swales on an otherwise even or slightly turtlebacked
slope (see fig. 5). Another unique feature is that each stringer originates at
the upslope end immediately below an 8-to IS-foot escarpment and at the
bottom of a small cirquelike topographic feature (see fig. 6). On the sharp
escarpment and immediately above it are found only small-diameter birch
and young white spruce. In stringer 1 immediately below the escarpment,
several diffuse springs were found which were the source of a small streamlet
which followed a channel for 150 yards before diffusing underground. Black
spruce and sphagnum mosses were found growing in some of the stringers
(table 5). These are typically bottom and north-slope habitat plants, as they
do better on more mesic sites than the typically drier condition usually
found on south slopes. The soil profile descriptions (table 6) show that the
surface horizon of the stringer site has a greater capacity to store soil mois-
ture than the burned area site. The deeper surface horizon and higher con-
tent of organic matter help make this possible.
Several Colman blocks were placed in the ground at duplicate study sites
in stringer 1 and in burned area 1. Figure 7 shows that the soil temperature
at the l-inch depth in midsummer was higher in the burned area by about
5° F. Figure 8 presents temperature profiles at various depths below the soil
surface. The maximum summer temperature at the 14-inch depth in the
187
t r
t
!
188
----------------------------
TABLE 5.-Vegetation descriptions of a mature white spruce study site com-
munity and a previously burned site
Spruce stringer 1
Community: Picea glauca
Associated species: Picea mariana, Betula spp., Alnus crispa, Salix spp.
Rosa acicularies
Sphagny,_mspp.,Pleuroziumschreberi
Density: P. glauca-252 trees per acre
P. mariana -26 trees per acre
Betula spp. -17 trees per acre
A. crispa -understory
Salix spp. -numerous small shrubs
D.b.h.: P. glauca-12 to 18 inches
P. mariana -3 to 6 inches
Betula spp. -5 to 11 inches
Height: P. glauca-55 to 80 feet
P. mariana -30 to 40 feet
Betula spp. -25 to 40 feet
A. crispa -6 to 1 0 feet
Salix spp. -2 to 4 feet
Age: P. glauca -150-to 180-year-old stand
P. mariana -60-to 1 05-year-old stand
Betula spp. -80-to 11 0-year-old stand
Notes: This community is a mature white spruce stringer. A continuous thick
moss cover was found on this site. Grass was found especially in areas
not shaded by trees. Springs were found at the head of this stringer.
Alder was thick in the openings. Most' of the trees were mature. Few
seedlings were present here. The slope in this stringer was 12 percent.
Burned area 1
Community: Betula spp., Picea glauca, Alnus crispa
Associated species: Populus tremuloides, Salix spp.
Pleurozium schreberi
Density: Betula spp. -478 trees per acre
P. glauca-356 trees per acre
Salix spp. -57 trees per acre
P. tremuloides -9 trees per acre
A. crispa -abundant
D.b.h.: Betula spp. -4 to 7 inches
P. glauca -3-1 /2 to 5-l /2 inches
P. tremuloides -4 to 5 inches
Salix spp. -3 to 4 inches
Height: Betula spp. -30 to 40 feet
P. glauca -25 to 40 feet
P. tremuloides -25 to 30 feet
Salix spp. -20 to 25 feet
A. crispa -1 0 to 20 feet
Age: Betula spp. -30-to 38-year-old stand
P. glauca -30 to 39 years
P. tremuloides -25 to 32 years
TABLE 6.-Soil profile descriptions of a mature white spruce study site and
a previously burned site
Spruce stringer 1
Community: Mature white spruce
Elevation: 2,100 feet
,A~pe~;t_: _So_u!h
Position on slope: Upper one-third
Slope: 12 percent
Organic matter content: A horizon-24 percent, C horizon-5 percent
Soil bulk density: A horizon -0.51 gram per cubic centimeter
C horizon -1.1 7 grams per cubic centimeter
Soil profile description: 6-4 inches, live common moss
4-0 inches, partially decomposed moss, coarse root
mat.
0-8 inches, A horizon. Dark brown silt. Coarse roots.
8+ inches, C horizon. Light brown gravelly loam.
Numerous channery fragments. Schist flaggy layer
8-1 0 inches. No permafrost down to 65 inches. High
percent channery schist from 1 0 to 20 inches.
Burned area 1
Community: Birch-white spruce-alder
Elevation: 2,1 00 feet
Aspect: South
Position on slope: Upper one-third
Slope: 8 to 12 percent
Organic matter content: A horizon-7 percent
B horizon - 4 percent
C horizon - 3 percent
Soil bulk density: A horizon-0.90 gram per cubic centimeter
Soil profile description: 3-1 inches, dead leaves
1-0 inch, partially decomposed leaves
0-5 inches, A horizon. Weak thin platy structure.
Light brown to yellowish-brown silt loam.
5-14 inches, B horizon. Light brown gravelly loam.
Thin platy structure. Channery and flaggy
fragments.
14+ inches, C horizon. Massive. Channery and flaggy
fragments numerous.
189
190
Figure 5.-Photo of the stringers from the bottom of the south-facing slope of the study
area. Note stringers are located in slight depressions or swales .
spruce stringer was 40° F., whereas, at the 16-inch depth in the burned area,
it was 43° F. Also, there appeared to be a somewhat greater temperature
spread within the profile between the two sites. These Colman blocks had
been installed about June I, with only I month for establishing equilibrium
prior to initiation of readings . Higher soil temperatures during the summer
months in the burned area are due to the destruction of the organic layer
and thus less insulation of the mineral soil (9). Also, the soil moisture is
lower in the burned site and would have the effect of increasing the soil
temperatures because of a lower heat capacity. Higher soil temperatures
would have the effect of increasing potential evapotranspiration in the
burned area over that in the stringer; thus, a more droughty condition would
result.
Figure 9 presents the soil moisture data from the neutron meter during
the summer of 1970. This summer was exceedingly wet, as is indicated by
the relatively straight curves over the entire summer. The burned area
averaged approximately 23 percent moisture by volume and the stringer 35
percent for the entire summer. The soil moisture was about 12 percent
higher in the stringer site than in the burned area. The higher moisture
content in the stringer is presumed to result from several factors. The water-
seeps at the head of each stringer are an important factor. Soil profile investi-
gations indicate that the spruce site has a higher moisture storage capacity.
The greater shading and moss layer resulting in the cooler temperatures in
the spruce stands are important. The spruce forest may use smaller quantities
of soil moisture for growth. Also, burning may reduce the rate of water
percolation into the soil (9).
Figure 6.-Photo of the sharp escarpment at the head of stringer 4.
191
192
ss• SoJ7 Temperature -!"Depth
-
-
50" -
4
Burned area_,-~ .. -
45° ~~[ \ -
/ \ -
ro., ,...Spruce stdnger / ~\ -
~· -
()" ~ ~ i' v ~' --
' -,_ ----::: --
30"
--
25 -
= -
20" 1W' 'ff! i~n 'f.f J'jy ~~Y '%/! Agfl 11 IJ/! 5~ ~~ Nov
/3
Time (Monlh/Oays) 1970
Figure 7 .-Summer soil temperature data at the l-inch depth for the stringer and the
burned sites.
45 .
40"
35 .
30"
5 v
4 s•
0"
s•
3 0"
Soil Temperature
'"I~ 5"' ;,• ...._,
14 11 ~·-·"'
'"IV
16".,-"
Jun
:JO
~---
·"'·
,. ...
~
~" ,.,
/
~,_'
.~·-
~
1--r ....
Time (Month/Ooys) 1970
~ r" Spruce stringer
~ ~ ~
~
\~urned area
·~ ~ I'-
Oct
8
Oct
28
Nov
IT
Oec
7
Figure 8.-Profile of soil temperatures at various depths below the soil surface for the two
study sites.
------·-----------------------···-----------··-·---------------·------~------------
45 Neutron Meter Surface Moisture Measurements
40
35
30
10
'jfY
..
---r--.~
Jun
/0
-
-
Jun
20
--
Jun
30
---
Time (Month/Days) /970
-.
""" """ "-., Spruce stringer
r---.... , 1--.... ,. ....
....... ·""
,.,. Burned area
~
A'ff'
Figure 9.-Neutron meter surface soil moisture measurements of the stringer and burned
sites during the summer period of 1970. Each entry is the mean of 10
determinations.
Colman blocks were also used to monitor the soil moisture throughout the
profile, and figure 1 0 shows that the burned area averaged about 40 percent
by volume and the stringer about 60 percent for the entire summer. The
percent moisture obtained from the Colman blocks is substantially higher
than that from the neutron meter. This discrepancy is apparently due to the
manner in which each device measures soil moisture. The neutron meter
measures the moisture in a given volume of space within the range of its
radioactive element. The results reflect the actual volumetric soil moisture
present within that "total volume." This includes soil particles, air pores, and
large stones, the latter of which are quite numerous on these sites, 35 to 40
percent of total volume.
The Colman blocks measure the moisture of the soil matrix (soil particles
only) in direct contact around the sensing device. For total moisture in the
soil profile, the Colman blocks, unlike the neutron meter, make no allow-
ance for stone content of the bulk profile. Thus, the reference volume is
different for the two methods. When the stone content is high, an adjust-
ment of the volumetric data for stone volume is appropriate for comparison
of the two sets of data. Table 7 presents this adjustment and shows the
correlation of the two methods after the Colman block data are adjusted for
stones. The adjusted moisture contents are surprisingly close for the Colman
and neutron meter methods, 37 and 35 percent for the stringers and 21 and
24 percent for the burned sites, respectively.
·-----------·-.. ·---··---·------·---
193
-\0 ~
TABLE 7.-Average seasonal soil moisture content within surface 6-9 inches expressing measurement technique comparisons
with stony material
Mean soil moisture
Colman blocks Neutron meter
Area Percent stones in
surface layer1 Percent by volume
measured Percent by volume Percent by volume
(on "soil" (adjusted for stones) measured
calibration)
Spruce stringer 40 61 37 35
Burned area 35 40 21 24
1 Estimated during field excavation, by volume.
I I• 1-1 !•lUI-•o,-F"!'"J"'"'Wil'~J[S'Of;' "II •<'f
----------
Colman Block Surface 6"Moisture Measurements
65
1+7"
..... v I-----.....
"' ~uce stringer
60
55
50 -.. -.. -
~.!.+5" Burned area ·--~----
___ .. ----~---........... 1-------
~~ S~t
Time (Month/Ooys) 1970
Figure 10.-Colman block surface-layer soil moisture measurements of the stringer and
burned sites during the summer period of 1970. Duplicate units at l-inch
and 5-to 7-inch depths are averaged for each entry.
The combined means of the two methods averaged over the entire summer
showed that the soil moisture was higher by 1 0 to 15 percent by total
volume in the stringer than the burned area. In a dry summer this difference
would be expected to be much greater.
The wetter surface soil in the stringers maintains a damp moss layer that
would not be very susceptible to burning. The higher surface-layer soil mois-
ture and the resulting greener and less combustible vegetation would seem to
be a highly important factor in preventing fires being carried by the organic
layer and understory vegetation as well as by the trees. This would have the
effect of inhibiting fires in the stringers.
Summary
A study of mature stringers in a fire-patterned landscape in the Caribou
Creek Research Watershed near Fairbanks, Alaska, has shown the stringers to
be homogeneous both within and among stands in regard to spatial arrange-
ment and age of the white spruce and birch. The understory of alder and
willow was also homogeneous within and among stringers. Within and among
the adjacent burned areas the composition, density, and age of the trees were
found to be very heterogeneous.
~-
195
196
-~~----------------------------~---------·-
The last severe fire which swept through the study area was approximately
40 years ago, around 1930. Fire-killed remnants that are still standing indi-
cate that the fire previous to the 1930 fire may have been 65 years before,
around 1865. There was no evidence that any moderate or severe fires have
gone through the spruce stringers, and they appear to have been fire-free for
over 200 years.
On the previously burned areas, a long-term cycling effect is indicated
which seems to perpetuate a birch-spruce community. Succession toward the
climax white spruce is always in progress, but because of frequent fires, the
climax condition has not been approached for many, many decades.
Apparently the microrelief is a significant factor wherein the stringers
have remained fire-free for so many years. All the stringers were found
growing in minute depressions or swales. This topographic effect and the
presence of a streamlet contributed to a higher soil moisture in the stringer
sites than was found in the adjacent burned areas. The combined means of
nuclear and Colman measurement methods averaged over the entire summer
of 1970 showed that the soil moisture was from I 0 to 15 percent higher
(total volume basis) in the stringer than the burned area. The soil tempera-
ture at the l-inch depth in the burned site was found to be 5° F. higher
throughout midsummer than the stringer site. The soil temperatures at lower
depths showed a similar trend.
The higher surface-layer soil moisture and the resulting thicker and wetter
moss and duff cover seem to be an important factor in preventing the entry
of ground fires in the spruce stringers.
-------------·---------
Literature Cited
1. Ahlgren, I. F., and C. E. Ahlgren. 1960. Ecological effects of forest fires.
Bot. Rev. 26: 483-533.
2. Clarke, G. L. 1954. Elements of ecology. New York: John Wiley and
Sons, Inc.
3. Covert, C. C., and C. E-. Ellsworth. 1909. Water-supply investigations in
the Yukon-Tanana region, Alaska, 1907 and 1908. U.S. Geol. Surv.
Water-Supply Pap. 228, 108 p.
4. Eyre, S. R. 1963. Vegetation and soils. Chicago: Adline Publishing Co.
5. Lutz, H. J. 1956. Ecological effects of forest fires in the interior of
Alaska. U.S. Dep. Agr. Tech'. Bull. 1133, 121 p.
6. Maisurow, D. K. 1941. The role of fire in the perpetuation of virgin
forests of northern Wisconsin. J. Forest. 39: 201-207.
7. Slaughter, C. W. 1971. Caribou-Poker Creeks Research Watershed-
background and current status. Spec. Rep. 157. Cold Reg. Res. & Eng.
Lab., Hanover, N.H.
8. Wahrhaftig, C. 1965. Physiographic divisions of Alaska. U.S. Geol. Surv.
Prof. Pap. 482.
9. Zasada, John C., and Robert A. Gregory. 1969. Regeneration of white
spruce with reference to interior Alaska, a literature review. USDA Forest
Serv. Res. Pap. PNW-79, 37 p. Pac. Northwest Forest & Range Exp. Sta.
t r ~
197
198
--------~-~-~
~o~-~ -~ -~-~--~~-~-~--~-~--~--------"-
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Apri113-14, 1971.
Effects of some intensive
forest management
practices on w bite spruce
e~osystems in in-terior Alas-ka
Abstract
This study reports the first 2 years' results of a thinning and fertilization
study conducted in a 70-year-old white spruce forest near Fairbanks, Alaska.
A 2. 7-fold increase in tree diameter growth during this period was attributed
to improved soil moisture, temperature, and nutrient regimes resulting from
the thinning and fertilization.
Introduction
Following destruction of the existing forest by fire, dense young stands of
trees may develop on upland sites in interior Alaska. In these stands, compe-
tition for light, soil water, and nutrients may be intense, resulting in de-
creased tree growth rates and high mortality. High stand densities reduce the
amount of radiation reaching the forest floor and thus, the temperature
regime.
Although intensive forestry practice in interior Alaska may be a number
of years in the future, it is important to know what effect these practices
may have on forest development. The objective of the present study was to
apply intensive management treatments to a dense 70-yea,r~old spruce stand
believed to be of fire origin and monitor changes in tree growth and selected
environmental factors regulating growth. This report summarizes the first 2
years' results.
Methods
DESCRIPTION OF STUDY AREA
The study area is located in the Yukon-Tanana uplands approximately 20
miles west of Fairbanks at an average elevation of 750 feet. Topography of
the site is moderately steep ( 15-to 20-percent slope) and characterized by
Keith Van Cleve
University of Alaska,
College, Alaska
199
-----~---------~ -------------------,-
---~---------
200
numerous, small swales. White spruce stands, suitable for experimental
purposes, occur between swales. Bedrock in the area is Birch Creek schist;
soil, developing in wind deposited loess, is a deep phase of the Fairbanks silt
loam.
FIELD METHODS
A 0.04-hectare control plot was established in this stand in September
1968. At this time, soil temperature units (Yellow Springs #401) were in-
st~led at_~r()und surface~ o~gal}i_c-n}inesal sgil bqundary,andJ5, 30, 6_0, and
90 centimeters in the soil profile. Atmospheric temperature beneath the
forest crown canopy was subsequently measured with a continuous record-
ing thermograph and standard maximum and minimum thermometers in-
stalled in a "bird house" weather shelter (3). Precipitation (within the forest)
was measured with duplicate standard IS-centimeter rain gauges and dupli-
cate 1.S-meter-long snow depth stakes. Three randomly located aluminum
neutron probe access tubes were used to assess soil moisture at 2S-centimeter
intervals to a depth of l.S meters in the soil profile. Tree diameter growth
was measured using band dendrometers installed on the tree boles at breast
height (6).
In April of 1969, three additional O.OS-hectare plots were established. The
treatments applied to these plots were unthinned and fertilized, thinned and
fertilized, and thinned only. The criteria followed in selection of trees to
remain on the thinning plots were: trees of large diameter and height classes
and of good vigor, and approximately equal spacing between remaining trees.
In some instances, the spacing criteria resulted in codominant or inter-
mediate crown class trees being left. Trees were felled with a chain saw
leaving approximately a IS-centimeter stump. Crowns and boles of felled
trees were sectioned into approximately 1-meter lengths and left on the
plots.
Fertilizer was applied at rates of 112 kilograms per hectare of N as
NH4 N03 , S 6 kilograms per hectare of P as treble superphosphate, and 112
kilograms per hectare of K as KC 1. Apparatus to measure environmental
parameters and diameter growth was installed in the thinned, fertilized plot
in the manner described for the control plot. Band dendrometers were in-
stalled on trees in the thinned only and the unthinned fertilized plots.
Since the time of plot establishment, atmospheric temperature, precipita-
tion, and soil temperature records were maintained on a weekly basis
throughout the year. Soil moisture readings were made weekly from April
through September. Diameter growth measurements were made weekly from
May through August. These measurements will be continued through the life
of the study.
Results
Soil chemical analysis indicated that the white spruce soil is moderately
acid and has N and P contents similar to selected forest soils in the Douglas-
----------------------
-~--------------~-----------
TABLE I.-Chemical properties of white spruce forest soil
Depth Exchangeable bases Total
(centi-pH N p CEC l Ca I Mg
exchangeable
meters) K bases
--------Percent --------------Milliequivalents per 100 grams ------
0-2.5 5.2 0.96 0.06 94.30 0.74 22.20 2.36 25.30
2.5-5.0 4.8 .58 .07 76.00 .76 14.10 1.86 16.72
5.0-14.0 5.4 .13 .05 22.21 .19 5.66 .81 6.66
14.0-24.0 5.6 .05 .04 12.81 .13 2.89 1.00 4.02
24.0-37.0 5.8 .03 .05 14.72 .13 3.05 1.42 4.60
37.0-52.0 5.9 .03 .05 10.03 .05 2.68 1.41 4.14
52.0-67.0 6.0 .03 .04 9.46 .03 2.98 1.60 4.61
67.0-83.0 6.3 .03 .05 10.03 .05 2.59 1.36 4.00
fir region of western Washington (4) and soils supporting Norway spruce and
Scots pine in Sweden (9). Exchangeable base status (K + Ca + Mg) varies
from 42.02 milliequivalents per 100 grams in the surface soil (0 to 5 centi-
meters) to 19.42 milliequivalents per 100 grams in the subsoil (5 to 52
centimeters, table 1).
Artificial thinning reduced stand density 4.4-fo1d, from 6,953 to 1 ,568
stems per hectare. Basal area was reduced 2.6 times from 41 to 16 square
meters per hectare.
By the end of the 1970 season, thinning with fertilization had increased
diameter increment about 2.7 times over the control (table 2, figs. 1 and 2);
thinning without fertilization increased diameter increment 1.6-fold over the
control. In addition, diameter growth was detected 1 to 2 weeks earlier in
thinned stands than in unthinned controls (figs. 1 and 2).
TABLE 2.-Effect of thinning and fertilization on diameter growth in a
70-year-old white spruce forest, 1970 growing season
Treatment
Control
Control+ fertilizer
Thinned
Thinned + fertilizer
Cumulative
diameter growth
-----Centimeters-----
0.07
.08
.11
.19
Increase over
control
1.1
1.6
2.7
--------------------
' ._ • ~
~-
201
202
·----------------~--~~--------
Marked change occurred in the soil temperature regimes as a result of
thinning. With one exception (average maximum air temperature May I to
November 5, 1969, 1.8° C. higher in control than thinned plot), average
atmospheric and soil temperature regimes during -1969 and 1970 for the
period May I to November 5 were slightly warmer in the thinned and
fertilized plot than in the control plot (table 3). On May 30, 1970, soil
temperatures in the thinned and fertilized plot compared with the control
1969 1970
Figure I.-Diameter growth and environmental factors in thinned and fertilized plot
of 70-year-old white spruce.
1969 1970
Figure 2.-Diameter growth and environmental factors in control plot of 70-year-
old white spruce.
"~~~~ --------------
TABLE 3.-Selected temperature and precipitation data obtained from white
spruce thinning plots
Control Thinned+
Time period and temperature fertilizer
1969 1 1970 1969 1 1970
-- - - --Degrees Celsius-- - - --
May !-November 5:
Average maximum air temperature 17.6 16.3 15.8 17.3
Average minimum air temperature .9 .9 2.2 1.1
Average soil temperature, 30 centimeters 4.5 5.2 5.9 5.6
Average soil temperature, 60 centimeters 3.5 4.1 5.0 5.1
May 30:
Maximum air temperature 22.7 19.0 25.0 21.0
Minimum air temperature -3.4 4.4 -3.4 4.4
Soil temperature, 30 centimeters 3.5 2.0 2.0 5.5
Soil temperature, 60 centimeters .5 .5 .5 1.5
August 28:
Maximum air temperature 19.4 19.0 20.5 23.4
Minimum air temperature 1.5 3.4 1.5 3.4
Soil temperature, 30 centimeters 6.5 8.7 8.0 10.9
Soil temperature, 60 centimeters 5.0 7.0 7.0 10.0
-------Centimeters-------
May 1-August 30, total precipitation 16.5 23.3 17.4 23.0
plot were 3.5° C. to 1.0° C. warmer at the 30-and 60-centimeter levels,
respectively, and on August 28, 1970, 2.2° C. and 3.0° C. warmer (table 3).
Slightly more precipitation was collected beneath the thinned and
fertilized stand (0.9 centimeter) than the control stand during the May to
November period in 1969. Only a 0.3-centimeter difference in precipitation
was detected during this period in 1970. From 5.6 to 6.8 centimeters more
precipitation occurred in thinned and control stands, respectively, during
this interval in 1970 than in 1969 (table 3).
Approximately 1 year following stand treatment, rooting zone soil mois-
ture contents in the thinned and fertilized plot compared with the control
plot were 9.0 and 5.8 percent higher at the 41-and 71-centimeter depths,
respectively, on July 17, 1970, and 12.7 and 6.5 percent higher on August
28, 1970 (table 4). An additional feature of the growing season soil moisture
regimes, which is evident in the thinned and fertilized but not the control
stand, is the consistently higher, fluctuating trend at 41 centimeters com-
pared with the lower, constant trends at the lower depths (figs. 1 and 2).
203
-
'
204
TABLE 4.-Selected soil moisture content data obtained from white spruce
thinning plots
Date and depth
July 17:
41 centimeters
71 centimeters
163 centimeters
August 28:
41 centimeters
71 centimeters
163 centimeters
Control
1969 1 1970
Thinned+
fertilizer
1969 1 1970
------------Volume percent water-----------·
12.0 16.0 18.0 25.0
12.0 10.2 13.0 16.1
22.0 30.2 14.0 17.5
20.0 13.8 28.0 26.5
11.0 9.0 15.0 15.5
20.0 18.5 14.0 14.5
Discussion and Conclusions
Exact details on nature of the seedbed following the assumed fire are not
available. However, it is probable that a combination of favorable conditions,
possibly including bare mineral soil and downed and decaying tree boles,
existed and contributed to extensive seed germination, seedling develop-
ment, and the present fully stocked stand. At the time the present study was
initiated, extensive natural thinning had occurred, leaving groups of
dominant to intermediate crown class trees surrounded by dense stands of
suppressed trees and dead stems.
Influence of the previous fire on mass of potential volatile nutrient ele-
ments, such as nitrogen in the forest floor and surface layers of mineral soil,
is difficult to quantify. No forest floor nitrogen determinations have been
conducted in the white spruce forest under consideration in the present
study. However, using determinations of forest floor nitrogen content ob-
tained in 73-and 130-year-old spruce forests in the Russian taiga (8) and
determination of soil nitrogen for the 70-year-old spruce forest in the
present study and a I 70-year-old upland spruce forest located in the same
vicinity, the loss of nitrogen from burning near the midpoint and end of
white spruce forest development can be estimated.
Hypothesizing a uniformly severe burn, in which the forest floor and
highly organic horizons in the surface layers of the soil profile (0-5 centi-
meters) are completely consumed, and the nitrogen contained therein lost,
the 70-year-old forest would lose about 21 percent or 778 kilograms per
hectare of the nitrogen contained in the forest floor and soil profile through
the rooting zone (68 centimeters). The 170-year-old forest would lose about
42.5 percent or 2,026 kilograms per hectare of the nitrogen contained in the
same portions of the forest floor-soil profile. Depending on the severity and
uniformity of burning of the forest floor and overs tory, these estimates may
be low or excessive. Furthermore, all the nitrogen contained in the forest
floor and mineral soil is not readily available to plants but is an indication of
the potential supply of this nutrient which can be released for plant use over
an extended time period. The figures are, therefore, estimates of loss of a
potential supply of nitrogen.
A further estimate of nitrogen deficit from burning can be obtained by
considering the difference between nitrogen in the forest floor and surface 5
centimeters of soil in the mature spruce forest (170 years) and at 70 years.
This amount, 1,248 kilograms per hectare or 26 percent of the nitrogen
contained in the forest floor and mineral soil at 170 years, may be viewed as
a nitrogen deficit from which the forest-soil system has not recovered 70
years following burning. The nitrogen deficit theoretically has been reduced
to about 22 percent by fertilization. However, much of this addition may
have been lost through leaching and denitrification. The amount of nitrogen
contained in the soil at present will have to be determined by soil analysis.
Although the deficit estimate is tentative, it is similar to estimates (I) of
losses of 67 percent and 507 to 1,685 kilograms per hectare of nitrogen for
burned forested areas in various geographic regions.
The relationship of forest thinning and fertilization to improved tree
diameter growth rate is well documented in the literature (2, 4, 5, 7). In-
creased growth for thinned trees is closely correlated with improved light,
soil moisture, and soil nutrient regimes (2, 7, 10, 11, 12). Because rates of
soil nutrient turnover may be depressed by low temperatures encountered in
taiga soils, forest fertilization in conjunction with thinning generally may be
of considerable importance in stimulating tree growth.
In northern latitudes, an additional factor of considerable significance to
tree growth is soil temperature. Soil temperature is critical in seasonal
physiological activity of tree root systems and physical-chemical processes
and soil microbial activity associated with cycling of elements required in
tree nutrition. The critical role of temperature and moisture in interior
Alaskan forest-soil-plant relations is emphasized by the fact that forest floor
and soil organic matter are undoubtedly the principal source of nitrogen for
plant nutrition. The rate at which nitrogen becomes available for plant use is
controlled by microbial decomposition and mineralization of the organic
matter. These processes are dependent on temperature and moisture. In-
creases in soil temperature and moisture content should provide more favor-
able conditions for organic matter mineralization and nutrient availability
for tree growth. In interior Alaska, an increase in soil temperature of several
degrees, as occurred in this study, may be of much greater significance to
tree growth than in southern latitudes.
The control of tree density in northern latitude postfire forests may be
t
E-
'
205
206
--~~~----·--------------·----
viewed as management of the forest-soil system for improved moisture, light,
nutrient, and temperature regimes with respect to tree growth. In the present
study, fire may have directly altered subsequent forest development by
adversely affecting the concentration of volatile nutrient elements such as
nitrogen which are contained in forest floor and soil organic matter. Fire
played an indirect role in forest development by promoting the present fully
stocked stand in which competition for moisture, light, and nutrients is
undoubtedly intense and where a low soil temperature regime may reduce
rates of nutrient cycling and inhibit tree root development. Although a more
extended time period is necessary to assess the full impact of thinning and
fertilization on the white spruce forest ecosystem discussed in this study, the
marked changes in temperature and moisture regimes and the increase in tree
diameter growth are definite indicators of the response of the forest to an
improved environment for growth.
Acknowledgment
This study is a cooperative endeavor between the Forest Soils Laboratory
of the University of Alaska at College and the Institute of Northern Forestry
of the Pacific Northwest Forest and Range Experiment Station at College,
Alaska.
-~--· -· -· ---------------·-~~-~-~~---~-
Literature Cited
1. Ahlgren, I. F., and C. E. Ahlgren. 1960. Ecological effects of forest fires.
Bot. Rev. 26( 4): 483-533.
2. Dell-Bianca, Lino, and Robert E. Oils. 1960. Some effects of stand
density in a red pine plantation on soil moisture, soil temperature a11d
radial growth. J. Forest. 58: 373-377. ·
3. Fraser, J. W. 1961. A simple instrument shelter for use in forest ecology
studies. Can. Dep. Forest., Forest ~es. Br. Tech. Note 113, 110 p.
4. Gessel, S. P., T. N. Stoate, and K. J. Turnbull. 1965. The growth behav-
ior of Douglas fir with nitrogenous fertilizer in western Washington.
lnst. Forest Prod., CoiL Forest. Res. Bull. 1, 204 p. Univ. Wash.
5. , T. N. Stoate, and K. J. Turnbull. 1969. The growth be-
havior of Douglas fir with nitrogenous fertilizer in western Washington.
In~t. Forest Prod., CoiL Forest. 2d Rep. Contrib. No. 7, 119 p. Univ.
Wash.
6. Hall, R. C. 1944. A vernier tree growth band. J. Forest. 42: 742.
7. Hunt, Fred M., and Donald L. Mader. 1970. Low density management -
a means to increase timber yields while using less soil moisture. Mass.
Agr. Exp. Sta. Bull. 588, 24 p.
8. Rodin, L. E., and N. I. Bazilevich. 1965. Production and mineral cycling
in terrestrial vegetation. 288 p. Edinburgh: Oliver and Boyd.
9. Troedsson, Tryggve, and Carl Olof Tamm. 1969. Small-scale spatial vaJi-
ation in forest soil properties and its implications for samppng pro-
cedures. Stud. Forest. Suecica 74, 30 p.
I 0. Zahner, Robert. 1966. Refinement in empirical functions for realistic
soil moisture regimes under forest cover. In William E. Sopper and
Howard W. Lull [eds.], International symposium on forest hydrology.
813 p. Pergammon Press.
11. . 1968. Means and effects of manipulating soil water in
managed forests. In Forest fertilization, theory and practice. 306 p. Pub.
Tenn: Valley Auth., Knoxville, Tenn.
12. . 1968. Water deficits and growth of trees. In T. T.
Koslpwski [ed.], Water deficits and plant growth. 233 p. Academic
Press.
207
208
--·---------·---------
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Apri113-14, 1971.
Fire., vegetation., soil.,
and barren-ground
caribou relations
in northern Canada
Abstract
The devastation of the winter habitat by forest fires has been suggested as
a possible cause of the decline of barren-ground caribou. Four areas in
northern Canada were selected for studying the effects of fire on lichen
rangelands. A literature review, forest cover maps, fire control records, and
examination of the forests themselves indicate that fire is a natural
phenomenon and not a new factor in the ecology of the region. During a
period that extended from 1961 through 1964, there were 1,250 known
forest fires that burned-over 5,005,872 acres of potential winter range. The
cover-map data on forest age classes suggested that the amount of destruc-
tion in recent years has increased.
The standing crop of usable forage and high-value lichens was determined
for six forest age classes. Destruction of the extremely slow-growing arboreal
lichens by fire must be considered a serious loss of caribou winter forage.
Burning did not affect all game populations alike as shown by the densi-
ties per acre of barren-ground caribou and moose pellet groups. In forests
over 120 years old, 722 caribou pellet groups per acre were found compared
with only 18 per acre on the 1-to 1 0-year age class. There were 49 moose
pellet groups per acre in the 11-to 30-year age class and only three per acre
in forests over 120 years old. Moose apparently preferred habitats in early
stages of succession, but barren-ground caribou favored those in later stages
of succession.
George W. Scotter
Canadian Wildlife
Service
Edmonton 15,
Alberta
----~----------
209
210
Introduction
Destruction of range by fire is one of several factors which might limit
barren-ground caribou (Rangifer tarandus groenlandicus) populations. Fites
caused by lightning or man generally affect only the winter range in the taiga
or northern region of the boreal forest; they are rare and usually limited on
1 the summer range because of the mixture of wet and dry tundra and barren
areas of rock or sand.
The Canadian Wildlife Service's intensive caribou research prograin in-
cluded an evaluation of the effects of fire on four key upland lichen winter-
ing areas within the taiga. Some primary objectives were to determine the
portion of burned winter range and any increase in recent years, the effects
9f fire on the usable standing crops of terrestrial forage and arboreal lichens,
the effects of fire on soil properties, and the effects of fire on range use by
barren-ground caribou and moose (Alces alces).
The Study Areas
The winter range of barren-ground caribou is restricted largely to the taiga
of northern Canada. It covers approximately 295,000 square miles in
northern Manitoba, northern Saskatc;hewan, northeastern Alberta and the
District of Mackenzie (fig. 1). Key wintering areas were studied intensively
because data collected there would presumably be applicable to the entire
winter rartge. Factors for selection of study areas were their importance to
caribou, their inclusion of burns of various ages, and therr accessibility by
airplane or boat. Federal and provincial biologists with previous experience
in caribou research helped select four areas of 5,000 to 8,000 square miles
each (fig. 1 ).
The forest on the winter range is largely coniferous, with deciduous trees
in disturbed regions. The major tree species are black spruce (Picea mariana),
white spruce (Picea glauca), jack pine (Pinus banksiana), white birch (Betula
papyrifera), tamarack (Larix laricina) and quaking aspen (Populus
tremuloides).
Methods
History and Extent of Forest Fires
Information on the history and extent of forest fires came from literature
pertinent to caribou and caribou ranges; fire control reports, giving number,
size and causes, from 1961 through 1964, provided by government agencies
in Alberta, Saskatchewan, Manitoba, and the District of Mackenzie; and
vegetation cover maps of the northern Saskatchewan study area, prepared
from recent aerial photographs. Forested and burned areas were classified as
\
' ............... '• --...J --1-----I
I i.Air£'
fAT'NABA~ I CA
I
I
I
I
\
' \
\
\
\
\ ',
I
I
----------· ---·-----
STUDY AREAS ~
SUMMER RANGE
I
I
I
I I I SASKATCHEWAN I
MANITOBA
I I
I :
I
ONTARIO
Figure 1.-Map of northern Canada showing the distribution of summer and winter
ranges of barren-ground caribou and the locations of major study areas.
1 to 15, 16 to 30,31 to 50, 51 to 75, 76 to 120, or over 120 years of age. A
dot-grid overlay on the cover maps was used to determine the area of each
class. The acres in an age class was divided by the number of years in that
class to estimate average annual destruction.
Effects of Fire on the Standing Crop of Forage
Effect of fire on the standing crop of usable forage was determined in
forest stands from each study area. A stand consisted of a spruce forest, or a
seral stage of white birch or jack pine which precede spruce, on an upland
~-
211
212
site with similar floristic composition and cover throughout. Forest stands
were divided into six age classes: 1 to 10, 11 to 30,31 to 50, 51 to 75,76 to
120, and over 120 years. Each stand was sampled by the weight-estimate
method of forage inventory (39, ·15).
The usable standing crop was measured on 126 forest stands in 38 loca-
tions on the study areas. Each stand contained five 1 00-foot-square sites
located, if possible, on the north, south, east and west slopes and on a level
area. The sites represented, as nearly as possible, the slope or level area under
consideration. Sites were 0.1 to 2 miles apart, depending on the topography
ana size of the forest stand in whiCh they were located. -
Each site contained 16 randomly selected circular sample plots stratified
so that four fell into each quarter of the site. The sample plots covered 9.6
square feet each.
Forage in the circular plots was clipped and weighed, or its weight was
estimated in grams, to determine how much usable standing crop was availa-
ble. Clipped forage was separated into species or groups before it was
weighed on a spring scale. Actual and estimated weights were recorded to the
nearest 5 grams of green weight.
The current growth of forbs, grasses, grasslike plants, and deciduous
shrubs was weighed. Leaves were removed from such evergreen shrubs as
mountain cranberry (Vaccinium vitis-idaea var. . minus) and common
Labrador tea (Ledum groenlandicum). Lichens were removed only to the
level where decomposition of the podetia was first observed as caribou
probably do not like the pungent odor of decaying podetia. Bryophytes were
not included as they are probably eaten only incidentally with other forage.
Green weights were converted to air-dried weights. Daily samples of each
major forage species were stored at room temperature in 1 00-gram amounts
until no weight loss could be detected. Lichens could be compared only on
an air-dried basis since their moisture content varied from 20 to 85 percent
with weather conditions. Workers were trained to check estimates against
actual weights before fieldwork began, and field estimates were checked
daily throughout the season.
Data on usable standing crops were related to the barren-ground caribou's
food habits in winter. Information gathered from Loughrey (33), Banfield
(1 0), Kelsall (27, 28, 29) and Scatter (43) was the basis for high, moderate
or low values assigned to shrubs and lichens as winter food. Summer observa-
tions of plants grazed during the previous winters and winter observations
supplemented this information. Assigned values were not based on nutritive
content. The high, moderate, and low values compare only the forage within
a group.
To determine the standing crop of arboreal lichens in the northern
Saskatchewan study area, the following method was used. Four black spruce
and four jack pine trees, each representative of its forest stand, were selected
as sample trees. The trees were felled and measured and their trunks divided
into 1 0-foot sections. Lichens were removed by hand from the trunk and
branches of each section. The relative abundance of different species was
noted, placed in cotton bags, air-dried at approximately 72° F., and weighed.
Five wedge prism readings were taken at each site to estimate the number of
trees per acre, and the diameter of trees viewed in each 360° horizontal
sweep was measured. Standing crops of arboreal lichens above and below the
1 0-foot level were calculated in pounds per acre.
Effects of Fire on Soil Properties
Forest fires destroy lichens and other forage, changing the ecological con-
ditions influencing plant growth and development. Changes in floristic
composition following fire may result from alterations in soil properties.
Chemical and physical changes after fire were therefore investigated at the
Saskatchewan study area.
Sampling sites were selected in mature black spruce forests, mature jack
pine forests, and on burned-over areas which formerly supported those
forests. Sites on burned-over and unburned areas with similarities of slope,
topography, drainage and soil parent material were sampled. Four burns
were sampled: two in jack pine and two in black spruce stands. The two
bums previously covered with jack pine forests were compared with a
mature jack pine-black spruce forest with similar slope, topography, and
drainage, but slightly different soil. The burned-over areas contained medium
textured, . pale brown sand; the jack pine-black spruce forest contained
medium loamy, grayish sand. Soils in this region are mainly composed of
podzols, podzol gleys, and peats.
Physical and chemical data were obtained from the sites in August.
Boulders and thin soil mantles sometimes precluded random sampling.
Temperature and erosion were studied. Six temperature readings were
taken, with a Weston soil thermometer, at 1-and 3-inch depths at each
location. The readings were taken in unshaded areas between 10:30 a.m. and
1 :00 p.m. Observations on erosion at each site were made from the ground
and from a low-flying aircraft.
A composite sample of 18 soil cores, three from each of six sites per
location, was collected from the 0-to 3-inch depth of mineral soil for
chemical analyses. Sampling was limited to a 3-inch depth because fire has
seldom changed the chemical composition of soils below the upper few
inches. The humus layer in burned-over areas had largely been destroyed and
could not validly be compared with that in mature forests, so it was not
sampled although such layers may be important sources of nutrients, closely
related to a site's productivity (19).
The Soil Survey Research Branch of the Canada Department of Agri-
culture, in cooperation with the Research Council of Alberta, made chemical
and pH determinations on the mineral soil cores. Methods of the Soil Survey
Research Branch were used to determine exchangeable hydrogen, sodium,
213
214
potassium, calcium, magnesium, and total cation exchange capacity. Extrac-
tions were as outlined by the Association Of Official Agricultural Chemists
(7). Calcium, magnesium, sodium, and potassium were determined by use of
the Beckman DU flame spectrophotometer with a model9200 flame attach-
ment and line-operated power supply unit as outlined by Baker (9), and with
the modifications suggested by Mathieu and Burtch (36), Mathieu and
Carson (37), and Carson, Mathieu, and Scheelar (16). A cleaning solution
(17) was used with the spectrophotometer. Total nitrogen was determined
by Prince's (40) Kjeldahl method, with mercury as a catalyst.
Available phosphorus was determined by extracting 5 grams of soil with
25 milliliters of 0.03-normal sulfuric acid and 0.03-normal ammonium
fluoride. Calorimetric measurements were then taken with a Fisher Model
No. A electrophotometer.
Field pH determinations were made with a Beckman Model 180 pocket
pH meter by inserting a glass electrode into mineral soil at the desired depth.
Composite soil samples, taken from the upper 3 inches of mineral soil, were
tested for pH in the Soil Survey Research Branch Laboratory by use of a
Beckman Model H2 pH meter. Before pH value was determined, a soil paste,
consisting of distilled water and dry sieved soil, was allowed to stand 15
minutes. Field and laboratory pH meters used in this study were compared
before the field season to ensure similar results.
Effects of Fire on Range Use by Caribou and Moose
Pellet groups were counted in each 9 .6-square-foot circular plot, used for
calculating the standing crop of usable forage, to compare use by barren-
ground caribou and moose in each forest age class. Six or more barren-
ground caribou winter pellets in one plot were recorded as a pellet group.
Kelsall (2 7) regarded six or more pellets as a group because barren-ground
caribou generally move while dropping their pellets, leaving a point of
concentration and several widely scattered pellets. Each pile of moose
summer droppings was considered a group. Pellet groups per stand were then
converted to pellet groups per acre.
Results
History and Extent of Forest Fires
Historical review.-Journals of early explorers and their modern day
counterparts confirm the prevalence of forest fires throughout the winter
range of barren-ground caribou in northern Canada. A review of references
concerning fires on the winter range of barren-ground caribou can be found
in other publications (42, 44).
Fire control reports.-Government agencies in the District of Mackenzie
and the provinces of Alberta, Saskatchewan, and Manitoba provided fire
control reports from 1961 through 1964 for the portion of winter range
---·-----
within their region. Total destruction reported during this period was
5,005,872 acres (45), about 2.7 percent of the winter range, a rather alarm-
ing total as the reports do not cover vast portions of the winter range.
Lightning apparently caused 72 percent of the fires (45). Changes in the
summer weather pattern in recent decades may have resulted in more light-
ning strikes or in conditions more suitable to the spread of fire. As would be
expected, most fires caused by man occurred near population centers.
Cover maps.-Forest cover maps, prepared from interpretation of recent
_a~rial photQgraphs, show thataverage destruction by fireinthe 1-to 15-, 16-
to 30-, 31-to 50-, 51-to 75-, 76-to 120-year age classes was 20,779, 14,080,
15,040, 14,310, and 6,599 acres per year, respectively. Fire destruction in
the 1-to 15-year age class was 1.4 times higher than in the 16-to 30-, 31-to
50-, 51-to 7 5-year age classes, in which the annual rate was almost constant;
and 3.1 times higher than in the 76-to 120-year age class. Destruction rate in
the 16-to 30-,31-to 50-, and 51-to 75-year age classes was 2.2 times greater
than in the 76-to 120-year age class. These increases coincide with mining
activity and white settlement. That some forests may have been burned more
than once during the years covered by the five age classes was not con-
sidered. Multiple burning would increase the area of young forests and
reduce the area of more mature forests.
The historical review and fire control reports reveal that ecological rela-
tionships between forest fires and barren-ground caribou have long existed.
The cover-map data on forest age classes suggest that destruction has in-
creased in recent years.
Effects of Fire on the Forage Supply
One of the most obvious effects of forest fires is the reduction in the
amount of available terrestrial and arboreal forage. Lichens, regarded as the
caribou's principal winter food (1 0, 28, 29), comprise nearly 60 percent of
the winter forage, according to data from rumen samples collected in
northern Canada (43).
Terrestrial forage.-Average air-dried weight of the usable standing crop
ranged from 177 pounds per acre in the 1-to 1 0-year age class to 1 ,085 pounds
per acre in the over 120-year age class (table 1). Grass and grasslike plants
and forbs yielded the highest amounts in the 1-to 1 0-year age class but gave
only a few pounds per acre in subsequent age classes. Shrub production was
low in the 1-to 1 0-year class but was reasonably consistent throughout the
remaining age classes. Lichens increased consistently from 3 pounds per acre
in the 1-to 1 0-year age class to 469 pounds per acre in the 51-to 7 5-year age
class. The amount was slightly less in the 76-to 120-year class because
caribou made moderate to heavy use of many forest stands. Despite similar
use in the over 120-year age class, usable lichens increased to 725 pounds per
acre. The high-value group included the so-called "reindeer" lichens, such as
Cladonia alpestris, C mitis, and C rangiferina. High-value lichens ranged
from an average 1 pound per acre in the 1-to 1 0-year-old class to an average
-~----------·
' t
L
215
216
TABLE 1.-Average standing crop of usable air-dried forage from 126 upland
forests in six age classes
Forage
type 1-10
Forest age classes (years)
120+
- - - - -- - - - - - -- - --Pounds per acre-- -- - - - - -- ----- -
Grass and
grasslike plants 35-8-t· 1 3 2
Forbs 68 9 2 3 4 7
Shrubs
High value 14 124 189 169 248 253
Moderate value 10 8 2 3 4 6
Low value 45 95 83 107 101 92
Subtotal 69 227 274 279 353 351
Lichens
High value 1 15 147 319 291 560
Moderate value 1 39 76 84 97 129
Low value 1 50 89 66 35 36
Subtotal 3 104 312 469 423 725
Others 1 2 ( 2) 0 ( 2) ( 2) ( 2)
Total 177 348 589 752 783 1,085
1 Others include club mosses and fungi. 2 Trace.
560 pounds per acre in the over 120-year age class. Moderate-value lichens
reached their peak abundance in the over 120-year age class, and low-value
lichens in the 31-to 50-year age class. Lichen abundance varied within each
age class but was generally related to maturity of the forest. Older forests
were occasionally less productive than younger forests in the same age class,
because tree density, soil type, caribou utilization, and other factors varied.
Lichen destruction is critical because of their slow succession and growth
rates and importance as winter forage for barren-ground caribou. Fire is
apparently as destructive to the major forage lichens as it is to the mature
conifers, when the recovery rate is considered. This study showed that major
forage lichens take from 70 to 1 00 years, and more, to regain their former
abundance and composition. The long recovery period is required for the
return of biological conditions suitable for lichen growth, for the succession
of lichens through a number of seral stages, and because of the slow growth
rate. In some sample sites in three of the study areas, the major forage
lichens attained an average growth rate ranging from 3 to 5 millimeters per
year, depending on the species (41).
----~-------------~-
TABLE 2.-Standing crop of arboreal lichens in black spruce and jack pine
forests in northern Saskatchewan
Forest type Below 1 0-foot
level
Above 10-foot
level Total
-- - - -- -- - - - - --Pounds per acre 1 - - - - - - - - - - - - - - -
Black spruce 605 464 1,069
Jack pine 339 1,490 1,829
1Air-dried weight.
Arboreal forage.-In northern Saskatchewan, the standing crop of arboreal
lichens within 1 0 feet of the ground was estimated at 605 pounds per acre in
mature black spruce forest and 339 pounds per acre in mature jack pine
forest (table 2). Arboreal lichens were less plentiful on many other segments
of the winter range. Lichens on fallen trees and lichens dislodged from above
the 1 0-foot level by wind or snow increased the available amount.
Arboreal lichens may be an important food source, particularly when
snow is deep or crusted with ice (42), and their destruction by fire must be
considered a serious loss of caribou winter forage. Alectoria, Evernia, and
Usnea are considered the most important of the arboreal lichens.
Effects of Forest Fires on Soil Properties
Soil temperatures.-Midday summer soil temperatures were higher in
burned-over areas than in unshaded, forested areas (table 3). Soil tempera-
tures on the four study plots averaged 10.5° F. higher at l-inch depths and
9.8° F. higher at 3-inch depths on recent burns than those on unshaded areas
in mature forests. Midday temperatures were consistently higher at l-inch
levels than at 3-inch levels. These temperature differences decreased between
the burned-over and forested areas as the time since the fire increased. Soil
temperatures were higher largely because fire burned away the insulating
unincorporated organic matter. In addition, the blackened surface absorbed
more heat during the long summer days, although this may have been partly
offset by higher radiation at night than in the forested areas.
Bauer (12) in California and Lutz (34) in Alaska have suggested that the
addition of charcoal to soil is a factor in its temperature increase. Tryon (52)
commented on the heat absorbing capacity of charcoal. Isaac and Hopkins
(25) felt that fire increased the capacity of soils to absorb heat, and
Kittredge (30) found afternoon March temperatures were more than 20° F.
higher at a l-inch depth on a burned-over area than on a forested area in
California. However, Shirley (46) reported no temperature differences on
burned and unburned quadrats in a jack pine stand.
217
·-----------------------·-----
~-
E-
" i=
218
TABLE 3.-Midday summer soil temperatures from unshaded areas in
burned-over and mature forests in northern Saskatchewan
Temperature Temperature
at l-inch Difference at 3-inch Difference
Description depth in depth in
(average of six temperatures average of six temperatures
readings) readings)
-----..... --------------OF. ---------------........... "'-
5-year-old burn 79.2 69.7
12.7 1 14.2 1
Mature black spruce 66.5 55.5
13-year-old burn 82.0 64.5
11.8 1 6.5 1
Mature black spruce 70.2 58.0
5-year-old burn 66.3 65.0
11.6 1 14.2 1
Mature jack pine-
black spruce 54.7 50.8
22-year-old burn 60.7 55.0
6.0 2 4.22
Mature jack pine-
black spruce 54.7 50.8
1 Significant at 1 percent.
2 Significant at 5 percent.
Erosion.-Erosiori was not serious after forest fires on the study area.
Destruction of plant covet, litter, and organic matter led to no more than
light sheet erosion. The low intensity of summer rainstorms, freezing of the
soil for about 7 months each year, and rapid colonization by a liverwort,
Marchantia polymorpha, and such mosses as Polytrichum piliferum and P.
juniperinum can account for the light erosion.
Any loss of soil from the thin mantles would be serious, but gully erosion
was noted only twice. In both cases, it was confined to sandy soils in
southern regions of the Saskatchewan study area. On two occasions, I
witnessed rainstorms on recent burns but noted little surface runoff from
rain pelting on exposed soil. Lutz (34) also found surprisingly little erosion
after fire in Alaska.
Wind erosion resulting in the formation of small sand dunes was noted on
two recent burns in southern sections of the Saskatchewan region but was
not considered a serious factor in soil loss.
·-----------------·----------------
~ • i
'
TABLE 4.-Chemical soil properties on burned-over and unburned forests in
northern Saskatchewan
"' i =
Exchangeable cations in .§ ~ "' .... ..c: ue milliequivalents, per CIS () ... () ....
Site :<» ·=
-o
I 00 grams of dry soil ..... fU;t: ~-a description 0 -u c; e ,se~~ :="' .... ~ 0
H I Na I K I Ca I Mg = ~~ 0 <"E.. tl.) E-<
-Parts per million-
5-year-old burn 4.1 0.1 e) 0.4 0.2 4.8 7.3 50 8.5
Mature black spruce 7.0 .1 e) .2 .4 7.7 11.8 100 1.0
13-year-old burn 3.4 .2 e) .2 .1 3.9 4.8 40 26.5
Mature black spruce 3.9 .1 e) .2 .1 4.3 4.9 40 14.5
5-year-old burn 1.9 .1 e) .4 .1 2.5 4.4 50 13.5
Mature jack pine-
black spruce 2.4 .2 e) .2 .1 2.9 3.2 30 e)
22-year-old burn 1.2 .1 e) .4 .1 1.8 2.9 20 37.0
Mature jack pine-
black spruce 2.4 .2 e) .2 .1 2.9 3.2 30 e)
1 Trace.
Cation exchange.-Total exchange capacity was lower in three of the four
burned-over areas than in mature forests (table 4). Total exchange capacity
increased slightly on one 5-year-old burn.
Exchangeable hydrogen was reduced on each bum. Godwin (21) demon-
strated reduced hydrogen ion concentration after burning on Vancouver
Island, British Columbia.
Exchangeable calcium increased on three sites and remained the same on
the fourth. Garren (20) recorded an: increase of calcium in his summary of
effects of fire on forest soils in the southeastern United States. Burning was
accompanied by an exchangeable calcium increase, to several times the
original figure (34), in Alaska.
In northern Saskatchewan, little change was noted in exchangeable potas-
sium, magnesium, or sodium. While studying effects of slash burning on soil,
Tarrant (50) observed that light burning, defined as the condition in which
fire chars but does not remove all organic litter from the surface, increased
exchangeable potassium, and had little appreciable effect on cation exchange
capacity. But severe burns greatly increased exchangeable potassium and
reduced cation exchange capacity. Burning of logging slash in western
Oregon and Washington increased soluble or available forms of potassium,
calcium, and magnesium (8).
"-" • r
---
219
220
Total nitrogen in mineral soils, as determined by the Kjeldahl method, did
not follow any apparent trend. It increased on one burn, was reduced on
two, and remained the same on the fourth. A review of literature also
revealed contradictory results. Barnette and Hester (11), Isaac and Hopkins
(25), and Austin and Baisinger ( 8) reported decreases in nitrogen, but
Heyward and Barnette (24) and Garren (20) reported increases. Tarrant (50)
reported light slash fires stimulated nitrification, and severe fires reduced
nitrogen content. Lutz (34) reported forest fires caused an immediate reduc-
tion in total nitrogen but an increase in available nitrogen.
Available phosphorus was present in greater amounts on the four burns
than in the adjacent unburned forests. Thorne and Peterson (51) believed
that the absence of large amounts of calcium increased the availability of
phosphorus. After fire in Alaska, the available phosphorus increased in upper
mineral layers (34). Austin and Baisinger (8) found that phosphorus in-
creased more than twofold on burned-over plots in Washington and Oregon.
Soil pH.-Under field conditions, soil pH values were higher in all burned-
over areas than in unburned forests (table 5). Acidity decreased at l-inch and
TABLE 5.-Soil pH in burned-over and unburned soils in
northern Saskatchewan
Laboratory Field Field
Site sample, sample, sample,
description 0-to 3-l-inch depth Range 3-inch depth
inch depth (median of (median of
six readings) six readings) .
5-year-old
burn 4.7 6.45 5.2-6.8 6.15
Mature black
spruce 4.4 5.0 4.2-6.3 5.6
13-year-old
burn 4.6 5.4 5.2-6.2 5.6
Mature black
spruce 4.5 5.2 4.7-5.2 5.4
5-year-old
burn 4.7 5.5 5.4-6.4 5.3
Mature jack pine-
black spruce 4.0 5.1 5.0-5.3 5.2
22-year-old
burn 5.2 5.9 5.4-6.2 5.8
Mature jack pine-
black spruce 4.0 5.1 5.0-5.3 5.2
Range
5.7-6.8
4.5-6.8
5.2-6.1
5.0-5.5
5.2-6.2
5.2-5.5
5.2-5.9
5.2-5.5
.
ij
--~-~--~-~~-~-------
3-inch depths in the burned-over soils. Although they had a lower pH than
field samples, laboratory samples showed the same trend of higher soil pH on
recent burns. Destruction of unincorporated organic material and addition of
alkalis from wood ash probably caused lower acidity.
Many workers have reported lower soil acidity after fire (35, 11, 20, 34,
13). In Sweden, pH values were higher for about 25 years on burned-over
areas than on adjacent unburned areas (53). The severity of the burn, how-
ever, may influence the number of years that the higher pH values will be
retained.
In previous studies, the effects of fire on soil properties have varied widely
with differences in soil type, climate, vegetation, and severity of the burn.
Ahlgren and Ahlgren (3) reviewed much of the literature on the effects of
fire on soil properties. Lutz's (34) investigation in Alaska is the only other
North American study made at a latitude comparable to northern Saskatche-
wan and in similar forest types I know of. From his study, Lutz (34, p. 78)
concluded in part:
No possible justification for uncontrolled wildfires can be found in
the realm of soil science. Such fires can never be justified or even
excused on the basis of beneficial effects on the soil, despite the
fact that fires may have favorable effects on certain properties.
The effects of fire on forest soils are favorable to certain soil properties
and unfavorable to others. To determine whether the deleterious effects
exceed the beneficial effects in northern forests, studies of lichen and
vascular plant ecology must be conducted.
Higher surface soil temperature on burned-over areas may be ecologically
favorable for the germination, emergence, and growth of certain plants.
Dubetz, Russell, and Anderson {18) found that higher soil temperatures
generally increased the rate and percentage of emergence of native and culti-
vated herbaceous species. How higher soil temperatures influence lichen
regeneration is unknown. The boreal Cladinae are moderately heat resistant
(4), but the higher summer soil temperatures and increased wind action
caused by the removal of vegetative cover may increase water evaporation,
which could result in desiccation of lichen stands. Lichens are strongly in-
fluenced by the abundance or lack of moisture ( 48). They can endure desic-
cation, but their metabolism, respiration, and assimilation are impaired by
insufficient water.
Soil pH is broadly correlated with the distribution of some plant species.
Wilde (54) gave a pH range of 4.7 to 6.5 as optimum for white spruce
growth, although other conditions can drastically modify the effect of soil
reaction. Many plants on the winter range, such as Labrador tea, are con-
sidered acidophilous. The pH of the substrate is generally believed to be an
ecological factor of prime importance in the distribution of lichens. Most
important forage lichens are found in habitats with pH values ranging be-
tween 4.5 and 5.5 (4).
~~~~------
221
~~---~-------
222
Little is known about the effect on most plants of the boreal forests of
increased or reduced nutrient supplies. The general increase of nutrients
resulting from ash may stimulate growth of some species and inhibit growth
of others. Ahlgren (2) found that oats and sunflowers grown in soil from
lightly burned-over areas increased in vigor and size compared with plants
grown in soils from unburned areas, but plants grown in soil collected after a
severe summer fire were no larger than those grown in soils from unburned
areas.
Ahlgren (1) suggested high concentrations of salts released from ash may
cause plasmolysis of root hairs and young roots and kill or retard growth of
seedlings. Heikinheimo (23) found that ash damaged spruce seedlings more
easily than pine seedlings.
The nutrient requirements and tolerance levels of lichens have received
little attention, but lichens may have specific mineral requirements (22).
"Reindeer" lichens obtained most of their water and nutrients from rain and
from the atmosphere (4), but soil quality was important during early lichen
growth. According to Ahti, most species avoid calcareous soils and prefer the
acid humus of podzols during germination. Addition of wood ash to lichen
stands in Russia proved harmful to lichens (6).
Infrequent fire may not be disastrous to the fertility of mineral soils in the
Saskatchewan study area. Higher postfire soil temperatures and reduced soil
acidity may stimulate or inhibit plant germination and growth, and studies
are needed to determine which are the plants affected. Many of the barren-
ground caribou's preferred food species are associated with sites having low
pH. The effects of soil temperatures on the emergence of such plants as
lichens require further investigation.
Range Use by Caribou and Moose
Fire in an upland spruce forest changes the community's cover of trees,
shrubs, bryophytes, and lichens into a tangle of fallen snags, exposed soil and,
later, into a cover of fireweed, grass, and shrub. This alteration in kind and
quality of plant cover is an indirect but important effect, as it subsequently
modifies wildlife populations.
TABLE 6.-Average number of caribou and moose pellet groups per acre in
forest stands by age classes
Kind of
pellet groups
Caribou
Moose
1-10
18 139
18 49
Age classes (years)
120+
149 498 633 722
26 13 13 3
--------------
Table 6 shows the densities per acre of barren-ground caribou and moose
pellet groups for the various forest age classes. Sampling yielded an estimated
722 caribou pellet groups per acre in forests over 120 years old, and only 18
per acre in those 1 to 1 0 years old. There were 49 moose pellet groups per
acre in the 11-to 30-year age class and only three per acre in the over
120-year age class. Moose apparently prefer habitats under 50 years old, and
barren-ground caribou those over 50 years old .
. In aerial observations, during the winter, of northern Saskatchewan and
thesouthern.MackenzieDistrict,it .. waseasytoseeJeedingcratersdug.inthe
show by barren-ground caribou. The frequency and distribution of these
feeding craters agreed with the pellet-group counts within various forest age
classes. The craters were largely confined to mature forests. A few trails and
feeding craters in recent burns were made by animals crossing from one
mature forest to another.
Forest fires improved ranges for moose in some areas of North America,
such as the Kenai Peninsula of Alaska, and resulted in higher moose popula-
tions (31, 32, 49). But a large moose population was not evident in the study
areas. The postfrre vegetation on upland sites contained only small amounts
of some browse plants preferred by moose, such as willows (Salix spp.).
White birch, a good moose food, was abundant in many of the younger
forest stands which had been disturbed by fire.
Discussion
The results of this study apply only to upland lichen forests, considered
by the writer to be the most susceptible to long-term destruction hy fire and
the most important single source of winter forage for barren-ground caribou.
The research was oriented to a single species and did not consider the advan-
tages or disadvantages to other animals of the region, except for rtlobse. The
study does not imply that fires are detrimental to all caribou habitat.
In the southern limits of the barren-ground caribou's winter range, fires
sometimes destroy thick carpets of bryophytes in upland forests thereby
making them more productive for lichens and other forage plants. But this
advantage is more important in the closed forest stands. Fires also improve
certain muskeg areas by destroying Sphagnum spp. and other bryophytes
which are replaced with forage preferred by caribou.
Ahti and H;epburn (5) suggested that lichen supply could be increased for
caribou in the northern boreal lichen belt of Ontario by burning the
Sphagnum fuscum peatlands, treeless bogs, or wooded muskegs; and further
south by burning the black spruce-feather moss forests and black spruce
muskegs. In-addition, they recommended removing black spruce seedlings
and thinning jack pine stands to keep the woodlands from reverting to a
black spruce-feather moss community. The upland lichen woodlands within
------------~--------------
223
' "--• . r
224
the barren-ground caribou's winter range are generally sparsely treed and
need no thinning to maintain a condition favorable to lichen stands. Some of
my research has suggested that fires may beneficially affect nutrient cycling,
increase summer soil temperatures, remove excessive humus layers, and
increase moose browse in many areas (42, 44). Kayll (26) summarized other
beneficial influences of fire in the boreal forest region of Canada, but some
of his comments may not apply to the taiga of that region.
Skoog (47) stated that range losses from fires in Alaska were greatly
mitigated hecause carihou_did noL depend on lichens in spruce forests for
forage, as they could utilize forages in other communities, such as tundra
and alpine meadows. He concluded that fires had little influence on fluctua-
tions in caribou numbers in Alaska. But there is a marked contrast between
much of the caribou's winter range in northern Canada and that in Alaska.
Burning of winter range in the relatively flat taiga of northern Canada might
send caribou many miles in search of forage; in Alaska, it might send caribou
only a short distance up the mountainside into the alpine region. Despite his
suggestion that lowlands are not used commonly by caribou, Skoog indi-
cated that in some areas, such as the Kuskokwim Mountains where alpine
areas are limited, burned sections may have inhibited a buildup of caribou
numbers.
Referring to the caribou winter range in interior Alaska, Leopold and Darling
(31) wrote " ... fire had played so dominant a part in destroying the lichen
range that we feel quite safe in attaching to that one factor the major blame
for caribou decrease." No attempt will be made to explain the contrasting
views of Skoog and Leopold and Darling regarding the role of fire on those
ranges. Perhaps such contrasting views reflect the need for detailed research
on the ecology of fire in northern environments, with a realization that data
from one region should not be applied to all northern areas.
Referring to Newfoundland caribou, Bergerud (14a, p. 39) concluded
that:
... forest fires in the past have increased the extent of winter
range by altering closed-canopy forests to lichen woodlands or
shrub-barrens, and prostrate sub-alpine spruce-fir thickets to
lichen-shrub barrens.
Bergerud (14, p. 941) also stated that:
For decades wildlife biologists have thought that caribou require
mature undisturbed lichen stands and that range destruction by
fire and overgrazing was the antithesis of caribou abundance. Yet
no proponent of this view has documented reduced reproduction
or increased mortality among lichen-deprived free-ranging caribou.
A significant correlation between lichen abundance and caribou
distribution is not sufficient evidence that lichen abundance also
limits caribou numbers.
Although there is little evidence to show a direct relationship between
range destruction and population declines in northern Canada, most of the
research started after the population was near its lowest level. It is therefore
impossible to obtain the evidence required by Bergerud. But studies do show
that fire can reduce the carrying capacity of lichen winter ranges. Climax
plant communities provide a large part of the food caribou prefer, and
lichens generally constitute a large portion of the winter diet, whether or not
they are necessary to the animal's survival. Ecological succession after fire
may well be more rapid in Newfoundland for it is further south than the
batten..;ground caribou's winter range· and has ·a maritime climate. In addi-
tion, Bergerud's (14a) comments on forest fires apply to closed canopy
forests and not the more open coniferous forests generally used by barren-
ground caribou.
Fire has decreased the potential carrying capacity of the barren-ground
caribou's upland winter range in the taiga and increased that of the moose
range, but the potential meat yields are not necessarily the same. Barren-
ground caribou spend approximately half the year in the tundra, which
might otherwise go unutilized, and half the year in the taiga. Moose are more
solitary than barren-ground caribou and depend on an appropriate mixture
of habitat within a localized area. The barren-ground caribou is unquestion-
ably the only native ungulate in the region adapted to using the high energy,
low protein lichen components of the upland taiga forest. This does not
imply that lichens are required but only that caribou are adapted to utilizing
them.
Symptoms of range deficiencies or starvation, such as poor physical condi-
tion, emaciation, lack of fat, severe outbreaks of disease, and parasitism,
have not been widespread, although some possible symptoms of nutritional
deficiencies have been identified. McEwan (38) reported that only 68.8 per-
cent of the females over 3 years old were pregnant during the severe winter
of 1961-62. Calf mortality has been high during certain years (29). Bergerud
(14, p. 941) questioned whether early calf mortality during certain years was
" ... an evolutionary imperative ... or an artifact of range destruction and
inadequate maternal nutrition, hence, low viability of calves at birth?"
Forest fires also have other indirect effects. For example, Banfield (1 0)
observed that recent burns, like topographical obstructions, deflect barren-
ground caribou migrations; Kelsall (2 7) and Scatter ( 44) have noted that
barren-ground caribou tend to avoid areas in the young successional stages
and are consistently more abundant in open mature spruce or jack pine
forests. Snow conditions, low forage production, and windfallen trees make
recent burns unattractive to caribou.
Conclusions
Although fire damaged winter range of barren-ground caribou before the
white man came to North America, its destruction rate has increased with
225
c -----------------
226
the growth of settlement and exploitation. In addition, changes in the
summer weather pattern may have contributed to the loss of potential
habitat. Fires adversely affect the standing crop of terrestrial and arboreal
) forage, apparently affecting lichens more seriously than other forage plants
because their reestablishment is delayed and their growth rates are slow.
Fire appears to reduce the winter range for barren-gro"\}nd caribou and
increase it for moose on upland forests studied. The biomass of cari~ou per
acre of mature forest appears higher than that of moose on early subclimax
forests on upland sites. Thus, for meat production, the upland' lichen forests
may be best spited to barren-ground caribou. ' ·
Research data from northern Canada are insufficient to determine the
extept to which forest fires have directly influenced the recent decline of the
barren-ground caribou popplation, But forest fires so affect the standing
crop of forage, pl~nt sucdession, and animal use that they may have been
arriong the principal causes of the decline. The present winter range, with its
vast fire-de~troyed areas, will not permit an increase in numbers to the level
of60 or 70 years ago. Reduced potential carrying capacity does not appear
to be the factor limiting the caribou population to the present low levels yet
may have reduced it to the point at which men, wolves, and other factors
could keep the numbers low.
f
References
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227
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,_
'
228
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26. Kayll, A. J. 1968. The role of fire in the boreal forest of Canada.
Petawawa Forest Exp. Sta. Inform. Rep. PS-X-7, 15 p.
27. Kelsall, J. P. 19 57. Continued barren-ground caribou studies. Can.
Wildlife Serv., Wildlife Manage. Bull. Ser. 1 , 12: 1-148.
28. .1960. Co-operative studies of barren-ground caribou
1957-58. Can. Wildlife Serv., Wildlife Manage. Bull. Ser. 1, 15: 1-145.
29. .1968. The migratory barren-ground caribou of Canada.
Can. Wildlife Serv., Monogr. 3, 340 p.
30. Kittredge, J. 1938. Comparative infiltration in the forest and open. J.
Forest. 36: 1156-1157.
31. Leopold, A. S., and F. F. Darling. 1953. Wildlife in Alaska. 129 p. New
York: Ronald Press Co.
32. and F. F. Darling. 1953. Effects of land use on moose
and caribou in Alaska. Trans. N. Amer. Wildlife Conf. 18: 553-562.
33. Loughrey, A. G. 1952. Caribou winter range study, 1951-52. Unpubl.
rep. in files of Can. Wildlife Serv., Ottawa.
34. Lutz, H. J. 1956. Ecological effects of forest fires in the interior of
Alaska. U.S. Dep. Agr. Tech. Bull. 1133, 121 p.
35. Marshall, R., and C. Averill. 1928. Soil alkalinity on recent burns.
Ecology 9: 533.
36. Mathieu, A. L., and N. Burtch. 1961. A modification for the Beckman
DU flame spectrophotometer. Can. J. Soil Sci. 41: 134-135.
37. and J. A. Carson. 1961. An air-jet stirrer for the Beck-
man DU flame spectrophotometer. Can. J. Soil Sci. 41: 136-137.
38. McEwan, E. H. 1963. Reproduction of barren-ground caribou Rangifer
tarandus groenlandicus (Linnaeus) with relation to migration. Unpubl.
Ph.D. thesis, McGill Univ., Montreal.
39. Pechanec, J. F., and G. D. Pickford. 1937. A weight estimate method
for the determination of range or pasture production. Amer. Soc.
Agron. 29: 894-904.
40. Prince, A. L. 1945. Determination of total nitrogen, ammonia, nitrates,
and nitrites in soils. Soil Sci. 59: 47-52.
41. Scotter, G. W. 1963. Growth rates of Cladonia alpestris, C mitis, and
C rangiferina in the Taltson River region, N.W.T. Can. J. Bot.
41:1199-1202.
'
I'
~-
F
229
230
42. .1964. Effects of forest fires on the winter range of
barren-ground caribou in northern Saskatchewan. Can. Wildlife Serv.,
Wildlife Manage. Bull. Ser. 1, 18: 1-111.
43. .1967. The winter diet of barren-ground caribou in
northern Canada. Can. Field-Natur. 81: 33-39.
44. .1968. Effects of forest fires on the lichen winter ranges
of barren-ground caribou in northern Canada. Unpubl. Ph.D. thesis,
Utah State Univ., Logan.
45. .1971. Wildfires in relation to the habitat of barren-
ground canoou in the taiga of northern Canada. Tenth Annu. Tall
Timbers Fire Ecol. Conf. Proc. 1970: 85-105.
46. Shirley, H. L. 1932. Does light burning stimulate aspen suckers? J.
Forest. 30: 419-420.
47. Skoog, R. 0. 1968. Ecology of the caribou (Rangifer tarandus granti)
in Alaska. Unpubl. Ph.D. thesis, Univ. Calif., Berkeley.
48. Smith, A. L. 1921. Lichens. 464 p. Cambridge: Univ. Press.
49. Spencer, D. L., and J. B. Hakala. 1964. Moose and fire on the Kenai.
Third Annu. Tall Timbers Fire Ecol. Conf. Proc. 1964: 10-33.
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Douglas-fir region. Soil Sci. Soc. Amer. Proc. 20: 408-411.
51. Thorne, D. W., and H. B. Peterson. 1949. Irrigated soils, their fertility
and management. 228 p. Philadelphia: Blakiston Co.
52. Tryon, E. H. 1948. Effect of charcoal on certain physical, chemical,
and biological properties of forest soils. Ecol. Monogr. 18: 81-115.
53. Uggla, E. 1958. Ecological effects of fire on north Swedish forests.
Almqvist & Wiksells Boktryckeri Ab., Uppsala. 18 p.
54. Wilde, S. A. 1958. Forest soils. 537 p. New York: Ronald Press Co.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-April13-14, 1971.
Natural regeneration of
interior Alaska forests-seed,
seedbed, and vegetative
d . .d . repro -net-Ion cons1 -erat1ons
Abstract
The forests of interior Alaska are a complex mosaic of stands which are,
to a significant degree, related to the fire history of this area. Following fire
the major interior forest tree species-white spruce, black spruce, paper
birch, quaking aspen, and balsam poplar-can regenerate from seed and/or
by vegetative means. Various aspects of seed production (including seedbed
considerations) and vegetative reproduction, as they may relate to burn
reforestation, are discussed.
Introduction
The forests of interior Alaska are a complex mosaic of stands which are,
to a significant degree, related to the fire history of this area. The five major
interior tree species, white spruce (Picea glauca (Moench) Voss), black spruce
(P. mariana (Mill.) B.S.P.), paper birch (Betula papyri/era Marsh.), quaking
aspen (Populus tremuloides Michx.), and balsam poplar (P. balsamifera L.)
are not fire resistant. However, as shown by Lutz (16), hardwood stands and
trees may be damaged less than spruce by fire because of the tree and forest
floor characteristics peculiar to each species. Fire also consumes tree seed
lying dormant on the forest floor. Thus, following a forest fire, the burned
area is totally or partially devoid of living trees, and any seed which was on
the ground and might have been of potential value in regenerating the site
has been consumed by fire. Therefore, complete or partial natural reforesta-
tion of the site is requisite to maintaining forests and trees as a dominant
form of vegetation.
Natural reforestation can result from seed or from vegetative reproduc-
tion. All interior Alaska species are capable of regenerating by means of seed
disseminated from trees (living or dead) on the burned area or in adjacent,
unburned stands. Vegetative reproduction of burns is probably lim~ted to
aspen, balsam poplar, and birch; obviously, the species must have been a
component of the prefrre forest in order to reforest the area bY this means.
This paper considers the initial phases of these two processes-that is, seed
John C. Zasada
Pacific Northwest
Forest and
Range Experiment Station
Forest Service, U.S.
Department of Agriculture
231
232
supply, seedbed requirements, and vegetative regeneration variables. The dis-
cussion is limited to these variables because they are basic to reforestation
and because entirely different factors must be considered in the next steps in
regeneration, i.e., seed germination and seedling growth and establishment.
Alaska-derived data are used where available; and, in this sense, this paper
updates and supplements Lutz (16). Where Alaska data are unavailable, other
information is used. Because of the varying intensity of research on the
different variables for each species, the quantity and scope of data vary
considerably among species. Most of the data p_!e_~e_tlted __ a,r~9§tiY~d_frJ)m
s-hidi.es conducted In unburned commercial forest areas. However, the vari-
ables to be considered are the most basic aspects of reforestation, and the
data presented should realistically characterize these factors as they relate to
reforestation of burns.
Tree Age and Seed Production
The relationship between tree age and seed production becomes important
when areas are subject to repeated fires and perhaps where the advance of
tree reproduction into large burned areas is of concern. Those species which
are able to produce seed in significant quantities relatively early in their life
cycle have an advantage over species which produce seed later. Age at which
first abundant and optimum seed production occurs may vary between
species. The age-seed production relationship may be altered significantly by
biological, climatic, and edaphic variables.
White spruce.-Cones have been observed on trees as young as 10 years,
and excellent seed crops have been observed in 20-year-old forest planta-
tions. However, it would appear that quantity seed production in natural
stands probably does not begin until age 40 years or older. The delay in
natural stands is probably more the result of variation in stand density and
competition than of inherent differences between trees in plantations and
natural stands. In Alaska, good cone crops have been observed on trees from
45 to 170 years old or older (33). 1
Black spruce.-Small quantities of seed have been observed on 10-to
IS-year-old trees in natural stands. Most stands over 25 years of age bear
seed regularly. Optimum age for seed production is between 50 and 150
years, but commercial seed crops occur in black spruce 250years old (10,
30): Individual trees in Alaska from 24 to 194 years old have been observed
to -produce good cone crops (500 or more new cones produced per tree in
1968).2
Paper birch.-Trees of this species begin bearing seed at about age 15
years; optimum bearing age is from 40 to 70 years (13). Alaska paper birch
1 This literature review covers many aspects of white spruce regeneration and, rather than cite
numerous papers, the literature review is cited.
2 Unpublished data on file at the Forestry Sciences Laboratory, Institute of Northern Forestry,
Pacific Northwest Forest and Range Experiment Station, College, Alaska.
stands ranging from about 45 to 100 years old have been observed to pro-
duce large quantities of seed (see footnote 2).
Quaking aspen.-The minimum commercial seed-bearing age is 20 years,
and the optimum is 50 to 70 years (26).
Balsam poplar.-No data were found on minimum or optimum seed-
bearing age for this species.
Summary.-These data indicate that white spruce may be the species
which begins abundant seed production latest in its life cycle. Optimum seed
production appears to begin at 40 to 50 years for the species for which data
are available. White and black spruce continue to produce seed up to at least
200 years of age. The short-lived hardwoods may not produce large quanti-
ties of seed much beyond an age of 100-120 years.
Ripening and Dispersal of Seed
Prompt regeneration of a burn is desirable, particularly when commercial
forest areas are burned and where unstable soil conditions (e.g., permafrost)
occur. The most efficient means of reforestation would result if seeds on the
trees at the time of the fire were available. It seems doubtful that seed would
ripen to any degree following death of the tree by fire; rather, it seems more
probable that seed-bearing organs would desiccate and, depending on their
maturity, either disperse or retain the contained seed. Thus, in order to have
the currently formed seed crop of value, it would probably have to be ripe at
the time of burning.
Seed on trees that have been killed by fire will be important only if not
burned or destroyed by heat generated by the fire. In order to affect seed-
bearing organs, the fire will have to burn in the crown of the tree or close
enough to it to generate high temperatures. Fires in hardwood stands may be
less intense than in spruce owing to the nature of the organic matter and a
branchless nature of the tree bole. Spruce stands (black spruce of all ages and
younger white spruce) are very susceptible to crown fires and possible burn-
ing of the cones because of vertical continuity of branches. However, it has
been observed that clusters of black spruce cones contain sound viable seed
after burning (1 0, 32). In general, then, it would appear that there could be
trees of all species within burns or there could be seed-bearing organs on
trees that still have potentially valuable seed after fire.
White spruce.-Although small amounts of seed may be ripe (i.e., will
produce seedlings) in late July, the majority of the seed does not ripen until
the end of the first or second week in August. Seed dispersal has been
observed as early as August 18 (a very warm, dry summer) and as late as
September 5 (an abnormally cool, wet summer). Seventy-five to 90 percent
of the seed crop is dispersed within 3-4 months of initial cone opening (34).
Black spruce.-Seed ripens in early September in southern black spruce
stands. Seed dispersal is more gradual than in white spruce (1 0). Lebarron
(15) reported that, on the average, 9 percent of annual dispersal occurred in
-------------~~~~~-
233
234
August, 19 percent in September, 38 percent from October to April, 13
percent in May, 14 percent in June, and 7 percent in July.
Paper birch.-Ripening occurs in late summer, from early August to mid-
September (13). Seed dispersal in southern parts of the species range has
been observed as early as July 4; however, peak dispersal normally occurs
between August and October. More than 90 percent of the seed crop is
dispersed by December (6). In Alaska, seedfall has been observed as early as
mid-July (see footnote 2). Large quantities have also been observed to be
dispersed after leaf fall. Reports of dispersal in early July in Alaska and
elsewhere indicate that seed. ripening may occur before August. . ..
Quaking aspen.-Seed dispersal occurs within a few days of ripening (26).
Dispersal has been observed in mid to late June near Fairbanks (see footnote
2). Graham et al. (8) report dispersal of aspen seed in late May in Michigan.
Balsam poplar.-Seed-bearing capsules mature during May or June, when
leaves are about two-thirds expanded; dispersal occurs shortly after (25).
Dispersal has been observed in early June near Fairbanks (see footnote 2).
Summary.-These data in conjunction with the following information on
fire occurrence (4) give some insight into the potential value of seeds on
trees in reforesting a burn.
Month
March
April
May
June
July
August
September
October
Cumulative percent of fires
1
3
22
61
86
94
98
100
Somewhat more than 86 percent of all fires occur before white spruce
seed maturity. Thus, it seems that little, if any, of the current seed crop of
fire-killed trees would be of value in reforestation. Seed dispersal from
adjacent unburned stands begins after most fires occur and could be used
efficiently.
Some black spruce seeds are available at all times because of semi-
serotinous nature of the cones. However, 90 percent of all fires probably
occur before the new seed crop matures. Thus, seed on the trees in older
cones is probably far more important than seed developing at the time of the
fire.
Paper birch is generally similar to white spruce except that reports of July
dispersal indicate that seed may mature by July of some years and may be of
value for regenerating burns occurring from mid-July to October. This would
also mean that any seed dispersed in July might be destroyed by the fire.
The report of ripening and dispersal of aspen and poplar seed in June
indicates that seeds of these species are probably available to regenerate
burns occurring in June and July. However, because of the limited life of the
seed (see below), these species are restricted in a different sense.
Quantity, Quality, and Dispersal
Distance of Seed
The size and quality of seed crops determine the amount of seed poten-
tially available for regeneration. Seed quantity and quality, in-conjunction
with seed dispersal distances, indicate the ability of the species to seed large
burned areas. Seeds of interior Alaska species are primarily disseminated by
wind. Other means of dissemination are over snow, in water, or by animals.
The importance of these secondary means of movement has not been quanti-
fied and may be of significant importance in regeneration of some burned
areas.
White spruce.-Seed production by white spruce in interior Alaska has
been observed to vary annually from near zero to 16 million seeds per acre.
Seed quality (percent of total crop potentially viable) has varied between 6
and 70 percent (average 45 percent). The higher percentages usually occur
during the better seed years. Estimated seed production by individual trees
in 1968 was between 54,000 and 64,000 seeds per tree (35,000-39,000
filled). Seed production by individual cones has varied between six and 62
seeds in Alaska (33, 34).
Maximum distance from the seed source for the spread of adequate
quantities of seed is about 150-200 feet (33). Limited data for Alaska indi-
cate that 50 and 90 percent of the seed dispersed from the top of a 60-foot-
tall tree landed 90 and 210 feet, respectively, from the base of the leeward
side of the tree (windspeed averaged 6 m.p.h.); only 2 percent traveled more
than 300 feet. Sixty-five percent of this seed was in the air 40 or less seconds
and 98 percent less than 80 seconds (see footnote 2).
Black spruce.-Because of the semiserotinous character of black spruce
cones, quantity and quality of seed can be considered from the current cone
crop as well as from previous cone crops. Lebarron (15) found an average of
about 180,000 viable seeds per acre in new cones and about 137,000 in
1-year-old cones in northern Minnesota swamp stands. About 2 percent of
the viable seed remained in 4-year-old cones, and some viable seed was still
retained in 15-year-old cones (1 0). Wilton (3 2) reported that, during a
60-day period after a fire on August 25, about 1.5 million black spruce seeds
(40-percent viability) were dispersed. Salvage operations caused approxi-
mately another 1 million seeds to be dispersed (20-percent viability). No
data are available on seed quantity in Alaska; however, the quantity of seed
produced by other species (e.g., white spruce and paper birch) appears to be
equal to or greater than production estimates elsewhere. Germination per-
centages for seed from 85 trees in interior Alaska averaged 47 (range, 7 to 86
percent) (see footnote 2).
235
236
Heinselman (1 0) reported 300,000 seeds per acre within a black spruce
stand, 19,000 at 100 feet from the stand, and virtually none beyond 300
feet. He concluded that effective dispersal is two or three tree heights from
the parent tree. This would indicate very limited distance of dispersal from
interior Alaska stands or individual trees because of the short trees.
Paper birch.-Birch seed production ir!t four undisturbed Alaska stands for
the period 1958-63 varied between 2.2 and 300 million seeds per acre. Average
annual production for all stands during this period was 92 million seeds per
acre. The quality of seed varied between about 1 and 42 percent (average 17
percent). The quantity of filled seed varied between 176,000 and 114 million
seeds per acre (see footnote 2). Percentages of filled seed were less than those
reported for this species in New England and other areas (29, 6).
Marquis (20) reported that quantity of birch seed reaching the ground two
tree heights from the bordering seed trees was only about 1 5 percent of that
within the stand. Based on Alaska data and above information, the amount
of seed reaching the ground at two tree heights from the seed source would
vary between about 26,000 and 17 million (average 14 million) seeds per
acre. Considerable quantities of seed may be carried farther in strong winds.
Quaking aspen.-Lutz (16) cited a northern European study that esti-
mated aspen stand seed production at between 162 and 202.4 million seeds
per acre. It was also reported that during a good seed year individual trees
may produce as many as 54 million seeds. The viability of fresh fertile seed is
high but normally of short duration. Barnes (personal communication)3 has
' found seed germination as high as 98 percent. Under favorable natural condi-
tions, seeds are believed to remain viable for a period of only 2 to 3 weeks
after maturity (26). Observations reported by Graham et al. (8) indicated
that seed viability may be of a longer duration.
The long, silky hairs attached to aspen seed allow dispersal over long
distances (26). No detailed information is available.
Balsam poplar.-Lutz (16) and Roe (25) reported that this species pro-
duces seed annually and in large quantities. No quantitative data were found
concerning seed quantity and quality in this species, but it may be similar to
that of aspen. Seed dispersal characteristics are also probably similar to those
of aspen.
Summary.-These data indicate that the three hardwood species produce
the greatest quantity of potentially viable seed, as well as having the greatest
potential dispersal distances. The two spruces may have equal or higher
percentages of filled seed but cannot produce seed in the tremendous quanti-
ties that the hardwoods are capable of producing.
The data reported for all aspects of seed production were collected in
commercial stands at lower elevation for all species. In these areas,
growing conditions are generally adequate for growth in all years.
3 Dr. B. V. Barnes, School of Natural Resources, Univ. Mich., Ann Arbor, Mich.
However, at higher latitudes and elevations, this may not be the case. In
1970, white spruce at 2,000 feet and higher in the Alaska Range produced
cones but, in some areas, did not appear to produce viable seed. Observations
at several times during the growing season indicated that cone and seed
development was at least 2 weeks to a month behind similar development in
the Fairbanks area (see footnote 2). Latitudinal and elevational effects on
cone and seed production are well established for Norway spruce (Picea abies
(L.) Karst.) in Europe (33). The point to be made is that seed quality may
decrease significantly and seed crops become less frequent with increasing
latitude and· elevation of stands,· thus decreasing regeneration potential
following fire on these sites.
Periodicity of Seed Years
Seed crop periodicity becomes important in determining how long regen-
eration may be delayed because of poor seed years. Depending on the species
and the quantity of seed produced annually, this variable can be very im-
portant for some species.
White spruce.-Excellent seed crops are known to have occurred in 1958
and 1970. Lutz (16) also reported observation of a good seed crop in 1952.
Between 1958 and 1970, two relatively good cone crops were observed as
well as three extremely poor years (see footnote 2 and Zasada and Viereck
(34)).
It is interesting to note that the excellent 1958 and 1970 seed crops
occurred in years immediately after two of the worst fire years on record
(4). This substantiates reported correlations between excellent seed crops
and warm, dry weather during the preceding year at the time of bud differ-
entiation (33).
Black spruce.-Heavy seed crops occur about once every 4 years and total
crop failures are infrequent in southern stands (1 0). Because good white
spruce seed crops appear to be separated by longer periods in Alaska than
elsewhere, it seems that this may also be true for black spruce. This variable
assumes less importance in black spruce because significant quantities of
viable seed are almost always present in the semiserotinous cones.
Paper birch.-Relatively large quantities of birch seed appear to be pro-
duced annually in interior Alaska with excellent crops occurring every 2 to 4
years (see footnote 2).
Quaking aspen.-Good seed crops are produced every 4 or 5 years with
light crops in intervening years (26).
Balsam poplar.-This species is believed to produce seed in large quantities
nearly every year (25).
Summary.-Birch, aspen, and poplar produce large seed crops at the most
frequent intervals. Good black spruce crops may occur more frequently than
those of white spruce but do not appear to be as large as those produced by
white spruce.
-·--------·-----~-----~--~-~-----------------------------~--·---·----~----------·-
237
238
Viable Seed to Seedling Ratio
The effectiveness of a seed crop will be determined in part by the number
of viable seeds required to produce an established seedling. This is a difficult
generalization to make because of the many variables which either directly
or indirectly affect the germination and establishment of seedlings. However,
data of this nature are potentially useful for estimating the quantities of seed
needed for forest establishment.
White spruce.-Between six and 12 viable seeds are required to produce
one established seedling on mineral soil seedbeds. (Seeds used in the various
studies reporting these data were generally treated to afford some degree of
protection against bird and rodent consumption.) On litter seedbeds, 800 to
1,000 seeds were required per seedling (33). Exploratory direct seeding on
mineral soil in Alaska with untreated seed indicated that between 12 and 24
seeds were required for each one-growing-season-old seedling produced (see
footnote 2). With significant mortality of these seedlings assured, it can
probably be expected that at least twice as many seeds may be required per
established seedling. Observations on undisturbed organic matter indicate
that seedlings are rare and establishment rarely, if ever, occurs on such
seedbeds.
Black spruce.-Johnston (14) reported two established seedlings per 100
seeds (95-percent viability) on undisturbed litter seedbeds; for compacted,
scalped, and burned seedspots corresponding values were 18, 29, and 22,
respectively. Lebarron (15) reported that 31 percent of seed sown produced
1-year-old seedlings on mineral soil, 6 percent on scarified and shaded duff, 4
percent on burned duff, and 1 percent on undisturbed duff. Richardson (24)
reported that sowing rates of 100,000 and 200,000 seeds (85 percent viable)
per acre produced adequate stocking and numbers of 5-year-old seedlings (80
percent and 3,600 seedlings per acre at 100,000 rate and 84 percent and
5,480 seedlings at 200,000 rate).
Paper birch.-Marquis et al. (21) reported that, depending on seedbed and
climatic conditions, between 20 and 400 birch seeds are required to produce
a single 1-year-old seedling. With additional mortality assured, this is probab-
ly a conservative estimate.
Quaking aspen.-Graham et al. (8) reported that, although seedlings may
germinate in great abundance, very few survive. Barnes (2) reported that
plots containing 18 to 450 newly germinated seedlings did not contain any
living seedlings after 2 years. Although it is generally believed that reproduc-
tion of aspen stands occurs most commonly by vegetative means, it is signifi-
cant to note that Lutz (16), Graham et al. (8), and Barnes (2) all report
numerous aspen seedlings on recently burned sites in Alaska, Michigan, and
northern Idaho.
Balsam poplar.-Seed of this species (as with aspen) does not exhibit
dormancy and appears to germinate immediately after dispersal; if seedbed
conditions are unfavorable, the seed dies. Lutz (16) reported balsam poplar
seedlings were abundant wherever mineral soil has been exposed and a seed
source is present. This species commonly regenerates by seed on river bot-
tom sites, but seedbed conditions on these sites are probably more desirable
than on burned areas.
Summary.-There is little doubt that the spruces, in general, have a signifi-
cantly lower viable seed to seedling ratio than hardwoods. However, when
considered in conjunction with the total number of viable seeds produced,
birch maintains a significant advantage over spruce in the number of seed-
lings th~t could potentially become established per average seed crop. Aspen
and poplar regenerate by seed under only the most ideal conditions and,
even then, the possibility of seedlings surviving is reportedly quite small. As
mentioned, however, the reports of seedling Populus stands in burned areas
may make this means of reproduction more important than it is usually
believed to be.
Caution must be exercised in general acceptance of these data for several
reasons. Mineral soil conditions in some burned areas in Alaska may be very
harsh and significantly increase these ratios; for example, the extremely wet
and relatively colder conditions which may occur on some sites (ridgetops
and areas of coarse textured soils and permafrost). In addition, the organic
matter data, with the exception of black spruce, were derived on relatively
thin organic layers (2-3 inches or less). Black spruce data were derived on
deep organic soils which generally have fairly good water contents. Organic
layers in Alaska before burning may be up to 10 inches or more in thickness
and if not consumed in burning will increase these ratios or may prevent
establishment in some cases.
Seedbed Requirements
Requirements which a seedbed must provide for germination and seedling
establishment are adequate moisture, sublethal seedbed temperatures, and
reduced competition. Whether a seedbed meets these requirements depends
on a number of interrelated variables among which are seedbed material,
aspect of seedbed, shading of seedbed, and seedbed water content (table 1).
Literature from other areas concerning optimum seedbeds for species occur-
ring in Alaska and general observation by the author and others indicate
that, under Alaska conditions, mineral soil comes closest to optimizing these
site variables, e.g., white spruce (16, 33), black spruce (15, 1 0), paper birch
(21), quaking aspen (26, 2), and balsam poplar (16, 25). However, organic
materials (e.g., humus, rotten wood) or mixed mineral soil-organic matter
supplied with adequate water throughout the growing season are excellent
seedbeds and may be even more desirable than mineral soil for rapid growth
and establishment of seedlings. It appears, though, that organic layers in
Alaska are not provided with enough water to make this material a good
seedbed.
The amount of mineral soil exposed by prescribed burning or wildfires
will vary with time and place of burn. Lutz (16) reported that mineral soil
---------~--
239
~~--~---~---------~------------~~-------------------
l..__
240
·--------·-··-----· --·-------
TABLE 1.-Seed, seedbed, and vegetative reproduction variables for white spruce,
Variable
Seed production-tree age
relationship in natural stands:
First abundant production
Period of optimum production
Seed ripening
Dispersal:
Initial
Duration
Seed quantity (seeds per acre)
Seed quality (percent
of total crop)
Dispersal distance
Periodicity of maximum seed
crops
Viable seed-seedling ratio:
Mineral soil
Organic matter 1
Seedbed requirements (i.e.,
believed most optimal under
Alaska conditions)
Vegetative reproduction:
Type
Capacity
White spruce
About 40 yrs.
40 to 170 or more yrs.
End of 1st to 2d week
in Aug.
Mid-Aug. to early Sept.
75-90 percent dispersed
by Dec.
0 to 16 million
6-70 percent
(average,
45 percent)
150-200 ft.
(2 tree heights)
10-12 yrs.
At least 12 to 24
800 to 1,000*
Mineral soil
Adventitious shoots*
Rare*
*Variables for which no Alaska data are available.
Black spruce
24 yrs.
24-194 or more yrs.
Early Sept.*
Sept.*
Throughout year*
300,000 to
2 million*
7-86 percent
(average,
47 percent)
2-3 tree heights*
Every 4-6 yrs. *
3*
100*
Mineral soil
Layering,
adventitious shoots
Common under disturbed
conditions but of doubt-
ful importance in burns*
Paper birch
15 yrs. *
45-100 yrs.
Maybe as early
as July, but
most commonly
Aug. to Sept.*
July to Sept.*
90 percent
by Dec.*
2.2 to 300
million
1-4 2 percent
(average,
17 percent)
At least 2 to 3
tree heights*
2-4 yrs.
20-400*
400+*
Mineral soil*
Sprouting of
dormant buds
Common
under some
conditions*
1 Thickness of organic layers generally less than 2-3 inches except in black sprnce where the data were derived from
studies on organic soils.
----~~-------~---~--~~------~
black spruce, paper birch, quaking aspen, and balsam poplar in interior Alaska
Quaking aspen
20 yrs.*
50-70 yrs.*
June*
June*
June-July*
Up to 200
million*
Maybe very high
(98 percent) viability
of short duration
under natural
conditions*
Long distance*
4-5 yrs.*
Probably many
thousands*
Impossible*
Mineral soil*
Root suckers
Very common in
fire-killed
aspen stands
*
*
Balsam
poplar
May or June*
Early June*
June*
*
*
*
Large quantities
every year*
Approaching
many
thousands*
Impossible*
Mineral
soil*
Root suckers
Common*
Summary and ranking by species
Earliest to latest
Birch > aspen ~ poplar > black spruce > white spruce
Longest to shortest optimum period
Black spruce~ white spruce > birch ~ aspen ~ poplar
Earliest to latest
Poplar > aspen > birch ~ white spruce > black spruce
Earliest Latest
Poplar > aspen > birch ~ white spruce > black spruce
Longest Shortest
Black spruce > white spruce ~birch > aspen ~ poplar
Largest Smallest
Aspen ~ poplar ~ birch > white spruce > black spruce
Birch ~ aspen ~ poplar > white spruce >black spruce
Farthest Shortest
Aspen ~ poplar > birch ~ white spruce > black spruce
Most frequent Least frequent
Aspen ~ poplar ~ birch > black spruce > white spruce
Least Most
White spruce ~ black spruce > birch > aspen ~ poplar
Least Most
White spruce ~ black spruce > birch > aspen ~ poplar
Aspen ~ poplar > birch > black spruce > white spruce
\' ' ~
t r
II-
,_
241
----------~--~---------"··-··--·------·------· ·------·--···--·-----·--~----··---~--------------------~----------~------·---~---------
242
exposure averaged 35 percent (range 0 to 100) of the area burned. Experi-
ence in western Canada with prescribed burning indicates that burning alone
does not produce an adequate seedbed for regenerating white spruce (33), In
British Columbia, it is recommended that in order to secure adequate white
spruce regeneration at least 60 percent of logged areas must have exposed
mineral soil seedbeds.4 These latter requirements are based on timber
management objectives and may be more or less than needed in burned
areas, depending on the desired density of the new forest.
Duration of seedbed receptivity is important because of the periodicity of
seed years. For some species (white spruce in particular), from 2 to many
years ,may be required to adequately stock an area. Seeding is generally most
successful on freshly exposed seedbeds. However, based on data from other
areas, seedbeds may be receptive for several years following initial exposure.
Vegetative Reproduction
Vegetative reproduction of several interior species is common. Regenera"'
tion from this source has a distinct advantage over seed regeneration because
it is not dependent on seedbed conditions and the sprouts or suckers have
the root system of the parent tree available as a source of food reserves and.
for water supply. Obviously, the disadvantage of this process is that the
species had to be growing on the site.
White spruce.-Weetman (31) reported a small spruce formed from an
adventitious shoot on the parent plant's root system. However, this occurs
only rarely and is of no practical importance to reforestation at present.
Black spruce.-This species reproduces vegetatively by layering (15, 10).
However, this type of reproduction is probably of little importance to refor-
estation of burned areas.
Paper birch.-Birch can regenerate by sprouting following logging or fire;
however, Hutnik and Cunningham (13) report .that this means of reproduc--
tion may be uncertain. They cite a study in Maine in which 77 percent of the
stumps sprouted but only 16 percent had live sprouts after 8 years. It also
seems that the source of sprouts (i.e., buds at base of parent tree) may be
susceptible to being killed directly or indirectly by fire. Lutz (16) and
Gregory and Haack (9) concluded that seed regeneration predominated over
vegetative reproduction for birch in Alaska.
Quaking aspen.-Gregory and Haack (9) have reported that the most com-
mon origin of trees of the aspen stands which they studied was believed to
be from root suckers. This is generally believed to be the case for aspen in
other areas, too (e.g., (26, 8, 2)). Graham et al. (8), Horton and Hopkins
(12), and Patton and Avant (23) report examples of abundant aspen sucker-
ing following fire. The source of suckers (aspen roots from 1 to several
inches below the soil surface) would appear to be much less susceptible to
4 Caribou Section, Canadian Institute of Forestry. Recommended forest practices for the central
interior of British Columbia. (Unpublished.) 29 p., 1969.
~·· --~--------------------~-~------------~-------------~-----~-----------·------~------
-
'
damage by burning or high temperatures generated during fires than the
source of birch sprouts.
The ability of aspen roots to produce suckers is great. Lutz (16) reported
as many as eighty 3-year-old suckers per milacre under a fire-killed aspen.
Aspen roots from Alaska trees have produced as many as five suckers per
centimeter of root under ideal conditions in the laboratory (see footnote 2).
Graham et al. (8) reported young sucker stands with 40,000 to 60,000 stems
per acre in the Lake States.
Balsam poplar.-Sucker regeneration of this species-following fire is be-
lieved more important than seed regeneration (16). Density of suckers and
capacity to produce suckers were not found but may be similar to that
reported for aspen.
Summary.-Aspen and probably balsam poplar exhibit the greatest ability
to reproduce vegetatively. In areas in which these species were components
of the prefire forest this probably constitutes the main means of reforesting
these species. Although birch has a capacity for vegetative reproduction, it is
probably not as important to the species as to aspen in burn reforestation.
The importance of vegetative reproduction to black spruce reforestation is
unknown but would seem to be much less important than seed reproduction.
Application of Data
These and similar data are useful for both applied and theoretical consid-
erations. Practically speaking, these data provide a quantitative basis for
evaluating reforestation potential of burned areas. Thus, an area could be
rated using such factors as seedbed conditions, seed source, and others. For
example, there is a strong indication that reforestation from seed by any of
the interior species may be extremely difficult unless a majority of the area
has an exposed mineral soil seedbed. In addition, burned areas farther than
150 to 200 feet from a seed source may not receive adequate seed for the
formation of well-stocked stands regardless of seedbed conditions. In addi-
tion, there is a possibility that upper-elevation burned areas may be further
limited because of limitations on seed maturation during some years. These
considerations suggest that manipulation of surface conditions may be re-
quired to efficiently utilize the seed available or that artificial seeding or
planting may be necessary to supplement or replace natural regeneration on
some sites.
These data can also be used in reconstructing past history of burn refor-
estation. For example, although most forest land is believed to have burned
at least once, much of the area has returned to forest cover. This would
indicate that, generally speaking, conditions created by fire in conjunction
with regeneration characteristics of these species have been adequate to re-
turn forest cover to predominance over varying time spans. Lutz (17) has
reported a decline in the occurrence of white spruce believed the result of
burning. Although this may be due, in part, to misconceptions of the impor-
tance of this species by early explorers, the above data indicate that white
----------~--
243
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L
&
244
----·-----·------~------··-·-··----
spruce in Alaska may be the most poorly adapted species from a postfire
reforestation standpoint. In almost every variable considered, white spruce
ranks last. Thus, as in other areas, it appears that fires may well have a
selective influence on reforestation, with hardwoods being favored to the
detriment of white spruce. These selective influences can be traced in part to
the factors discussed in this paper, that is, seed, seedbed, and vegetative
reproduction variables.
Literature Cited
1. Andrejak, G. E., and B. V. Barnes. 1969. A seedling population of
aspens in southeastern Michigan. Mich. Bot. 8: 189-202.
2. Barnes, B. V. 1966. The clonal growth habit of American aspens.
3.
Ecology 47: 439-447.
-----· 1969. Natural variation and delineation of cones of
Populus tremuloides and P. grandidentata in northern lower Michigan.
Silvae Genet. 18: 130-142.
4. Barney, Richard J. 1969. Interior Alaska wildfires 1956-1965. USDA
Forest Serv. Pac. Northwest Forest & Range Exp. Sta., 47 p.
5. Bjorkbom, J. C. 1967. Seedbed-preparation methods for paper birch.
USDA Forest Serv. Res. Pap. NE-79, 15 p. Northeast. Forest Exp. Sta.
6. Bjorkbom, John C., David A. Marquis, and Frank E. Cunningham.
1965. The variability of paper birch seed production, dispersal, and
germination. USDA Forest Serv. Res. Pap. NE-41, 8 p. Northeast. Forest
Exp. Sta.
7. Girouard, R. M. 1970. Rooting plain and heel cuttings of spruce. Plant
Propagator 16: 7-12.
8. Graham, S. A., R. P. Harrison, Jr., and C. E. Westen, Jr. 1963. Aspens-
phoenix trees of the Great Lakes Region. 272 p. Ann Arbor: Univ.
Mich. Press.
9. Gregory, R. A., and P. M. Haack. 1965. Growth and yield of well-
stocked aspen and birch stands in Alaska. USDA Forest Serv. Res. Pap.
NOR-2, 27 p. N. Forest Exp. Sta.
----·--~----~-~---~------
-------------------
10. Heinselman, M. L. 1957. Silvical characteristics of black spruce (Picea
mariana). USDA Forest Serv. Lake States Forest Exp. Sta. Pap. 45,
30p.
11. Horsley, S. B., and H. G. Abbot. 1970. Direct seeding of paper birch in
strip clearcutting. J. Forest. 68: 635-638.
12. Horton, K. W., and E. J. Hopkins. 1965. Influence of fire on aspen
suckering. Can. Dep. Forest. Publ. 1095, 19 p.
13. Hutnik, R. J., and F. E. Cunningham. 1961. Silvical characteristics of
paper birch. USDA Forest Serv. Northeast. Forest Exp. Sta. Pap. 141,
24p.
14. Johnston, W. F. 1967. Effect of vegetation and surface condition on
artificial reproduction of black spruce in a deforested swamp in north-
central Minnesota. Ph.D. thesis, Univ. Mich. Ill p. Diss. Abstr.
67-17788.
15. Lebarron, R. K. 1948. Silvicultural management of black spruce in
Minnesota. U.S. Dep. Agr. Circ. 791, 60 p.
16. Lutz, H. J. 1956. Ecological effects of forest fires in the interior of
Alaska. U.S. Dep. Agr. Tech. Bull. 1133, 121 p.
17. . 1963. Early forest conditions in the Alaska interior: an
historical account with original sources. USDA Forest Serv. N. Forest
Exp. Sta., 74 p.
18. Maini, J. S., and K. W. Horton. 1966. Vegetative propagation of Populus
spp. 1. Influence of temperature on formation and initial growth of
aspen suckers. Can. J. Bot. 44: 1183-1189.
19. Marquis, D. A. 1966. Germination and growth of paper birch and yellow
birch in simulated strip cuttings. USDA Forest Serv. Res. Pap. NE-54,
19 p. Northeast. Forest Exp. Sta.
20. . 1969. Silvical requirements for natural birch regenera-
tion. Birch Symp. Proc., p. 40-49. Univ. N.H., Durham.
21. , D. S. Solomon, and J. S. Bjorkbom. 1969. A silvicultural
guide for paper birch in the Northeast. USDA Forest Serv. Res. Pap.
NE-130, 47 p. Northeast. Forest Exp. Sta.
-c
245
246
22. Nienstaedt, H. 1957. Silvical characteristics of white spruce. USDA
Forest Serv. Lake States Forest Exp. Sta. Pap. 55, 23 p.
23. Patton, D. R., and H. D. Avant. 1970. Fire stimulated aspen sprouting in
a spruce-fir forest in New Mexico. USDA Forest Serv. Res. Note
RM-159, 3 p. Rocky Mt. Forest & Range Exp. Sta.
24. Richardson, J. 1970. Broadcast seeding black spruce on a burned cut-
over. Can. Forest Serv. Dep. Fish. & Forest. Publ. 1270, 14 p.
25. Roe, E. I. 1958. Silvical characteristics of balsam poplar. USDA Forest
Serv. Lake States Forest Exp. Sta. Pap. 65, 17 p.
26. Strothman, R. 0., and Z. A. Zasada. 1957. Silvical characteristics of
quaking aspen (Populus tremuloides). USDA Forest Serv. Lake States
Forest Exp. Sta. Pap. 49, 26 p.
27. Sutton, R. F. 1969. Silvics of white spruce (Picea glauca (Moench)
Voss). Can. Dep. Fish. & Forest. Forest. Br. Publ. 1250, 57 p.
28. Tew, R. K., N. V. Debyl, and J. D. Schultz. 1969. Intraclone root
connections among quaking aspen trees. Ecology 50(5): 920-921.
29. USDA Forest Service. 1948. Woody-plant seed manual. U.S. Dep. Agr.
Misc. Publ. 654, 416 p.
30. Vincent, A. B. 1965. Black spruce-a review of its silvics, ecology, and
silviculture. Can. Dep. Forest. Publ. 1100, 79 p.
31. Weetman, G. F. 1961. An adventitious shoot formation from a white
spruce root. Pulp & Pap. Res. Inst. Canada, Res. Note 22, 4 p.
32. Wilton, W. C. 1963. Black spruce seedfall immediately following fire.
Forest Chron. 39: 477-478.
33. Zasada, John C., and Robert A. Gregory. 1969. Regeneration of white
spruce with reference to interior Alaska-a literature review. USDA
Forest Serv. Res. Pap. PNW-79, 37 p. Pac. Northwest Forest & Range
Exp. Sta.
34. and Leslie }... Viereck. 1970. White spruce cone and seed
production in interior Alaska, 1957-68. USDA Forest Serv. Res. Note
PNW-129, 11 p. Pac. Northwest Forest & Range Exp. Sta.
------·------------------------
Fire and
Resources in
the Subarctic -
Panel Discussion
247
248
~~-~----~----~----------------------~----~
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
Introduction
In preparing for this symposium, discussion inevitably turned to the many Charles W. Slaughter
facets of wildfire in the subarctic which should be considered-material, U.S. Army Cold Regions
philosophical, economic. For instance, how do we put a "value lost" number Research & Engineering
on a burn north of the Yukon River? What impacts do fire operations have Laboratory
on the economy of Fairbanks? On the economy and village structure of Fairbanks, Alaska
Galena? Of Chalkyitsik, or Unalakleet, or Shungnak? Does the utilization of
village fire crews disrupt or alter social structures or native culture? In a
more direct sense, if the men of the village spend the summer with a
Fairbanks-based fire crew, will high-quality ivory carvings be available for the
tourist market?
In a different vein, the entire questions of fire history and the role of fire
in subarctic ecosystems remain open for exploration-the pioneering work of
H. J. Lutz reinforces the questions. Does fire over permafrost terrain result
in melting of the frozen ground from increased exposure to sunlight and
increased radiation absorption by blackened surfaces, or might a shallower
"active layer" (depth to permafrost) result, as suggested in a recent Russian
paper? Do moose benefit from increase of browse species following fire in
lowlands? What about water fowl nesting in the same lowlands? Smoke from
widespread fires obscures sunlight, impedes scenery-watching, and may cur-
tail military and commercial air traffic~even boat traffic. An acquaintance
recalls traveling by river boat from Fairbanks to Minto in August of 1969,
and being unable at some points to see either river bank, let alone landmarks,
thanks to the thick pall of smoke hanging in the lowlands. Does. public
policy take full account of this complex of questions about fire's role?
One could go on with such questions, of course. In any case, it was clear
that this symposium would not give "the answer" to the multitude of prob-
lems associated with fire. Research results are available on some facets, as
preceding phases of this meeting will attest. Other areas are untouched by
critical thought, let alone research of any depth.
In this frame of mind, it was resolved that a panel discussion, with time
for mutual give-and-take by all symposium participants, might be useful. The
title was left as broad as possible~"Fire and Resources in the Subarctic."
The panelists were asked only to share whatever thoughts they felt appro-
priate, within the framework of their experience, for the benefit of us all.
I wrote a letter to Al Comiskey in response to one he had written to me Roger A. Sylvester
stating that someone should present a paper at this symposium on how fires Bureau of Indian Affairs ~
affect the economy of native villages. I said I could not present a paper but Juneau, Alaska '
would serve on a panel discussion. Yesterday Chuck Slaughter caught up
with me and said, "You're on that panel."
249
-------~ --~ ·------------~
250
Richard Barney stated previously in his paper that $3.6 million was earned
in firefighters' wages last year in Alaska. The majority undoubtedly went to
trained local native crews. At the recent meeting of area foresters of Bureau
of Indian Affairs (BIA) in Phoenix, the Albuquerque BIA area forester re-
ported earnings of $1.4 million and the Billings area reported $1.4 million in
firefighters' wages for 1970. Consequently, there is considerable income
going to Indians and Alaska native people as firefighters.
I was given a proposal by Al Comiskey which has been bounced around
many times: "Is there any way that we could spread out the sporadic money
that the firefighters earn to year-round income?" In recent years, these
wa_ges have been .of a "boom or bust" nature. Firefighters earned consider-
able money and sometimes spent it all before they returned to the village.
Bureau of Land Management (BLM), the primary employer, has improved
the situation somewhat in recent years. It now mails firefighters' checks
directly to their village addresses.
In response to the question of firefighters' wages spread out to year-
round, ideally as we see it, firefighters' income should supplement another
income and not be the main source of annual income. However, in Alaska
this money is often the main source of income for many people. In our
recent BIA forestry meeting in Phoenix, it was brought out that we were
encouraging bad work habits by ~xpecting firefighters to sit around in their
villages and waif for a fire rather than search for a year-round job. I don't
think ~his is as true in Alaska as it is in other areas. I can't recall offhand
what I said in my letter to Al Comiskey, but the general trend of my
thinkingon this guaranteed wage was that it is like the national problem; we
ali talk about "a guaranteed annual minimum wage." Maybe it's communism
or socialism, and we in BIA don't wish to encourage such a system if native
people can get good year-round jobs.
Some of the basic effects of fire on the native economy I have written
down are as follows: Firefighters receive considerable income when it is
needed. It is intermittent and it's good. They like the work and to many of
them it's a status symbol in the village. I've worked with Indians the last 20
years, including the Apaches and Zunis, and all are very proud of the status
they have acquired as firefighters. One of the negative effects of firefighting
in Alaska is that when the men are firefighting no one lays in the food
supplies for winter or puts up the fish. It has been proved that our BIA
welfare assistance load is heavier in winters following a season of good fire
income than it is in years with lesser fire income. This also applies to the
fishermen; summer money is quickly spent and then the search starts for
another source for the winter time. Another negative aspect is that the
Government does not withhold income tax from firefighters' wages. (Curt
McVee can check me on this.) Most places they have never had withholding
statements. This year the Government sent out a few withholding statements
and the recipients did not know what to do with them. Another thing, life
insurance is rather skimpy.
We who hire, pass firefighters around as bodies rather than people. Two
Indian firefighters recently died on a fire in North Cascades National Park.
These people had passed from agency to agency; and when they fell in a
creek and drowned, investigations showed that they had been without sleep
for 36 hours. These are things we somehow hope to improve as years go by.
None of the hiring agencies would have counted this incident as 36 hours
without sleep as the firefighters had traveled by bus and that counts as sleep
time. You will agree that it is pretty hard to count bus riding as sleep time.
We have been trying in our BIA organization and I think Curt has too, to
bring Indians into more year-round positions. We are also trying to work
something like a shadow program at BIA in all operations so that when we
old duffers retire, we will have trained Indian fire control officers and others
skilled in running these programs. Some of the native people are shy when it
comes to issuing orders to Caucasians, but not all. We hope to build their
self-confidence in decisionmaking, for most Indian firefighters have been to
more fires than anyone except possibly Ed Komarek. Thank you.
For my part on this panel, I have chosen to introduce to you preliminary Ross W. Wein
data from one of our fire studies conducted last summer in Alaska and in the Department of Botany,
Yukon Territory. In contrast to most of the other papers, this study deals University of Alberta,
with a plant community that occurs both in the tundra and in the forested Edmonton, Alberta
regions of the North. Professor L. C. Bliss and I had been studying plant
production on the Eriophorum tussock tundra when one of our study sites
was burned in the June 24, 1969, fire, at Mile 107, Elliott Highway, Alaska.
Plant regrowth was so rapid that we felt it would be valuable to follow
secondary succession, provided we could find similar sites that had burned in
different years.
The Eriophorum tussock community consists of a matrix of Eriophorum
vaginatum L. (cottongrass) with heath species and varying amounts of
lichens and mosses. It is commonly found as an extensive tundra community
from the North Slope of Alaska, east to the Northwest Territories. South of
the tundra, it is found in areas of restricted drainage in the taiga. The
accompanying soils are acidic, peaty, and often underlain by permafrost.
Four study sites that had been burned for 1, 2, 2, and 4 years were
located in 1970. Two of these were true tundra, and two were in treeless
peaty soil of the taiga. Measurements of plant cover, active layer depth,
seedling density and plant production were made on both burned and un-
burned communities that were separated by either a road or a fire guard.
The fire in all cases had been severe enough that all aerial woody and
herbaceous plant material and the litter were consumed. The tightly packed
tussocks were charred but not burned, and little peat was burned. All mosses
were killed; but very often, mats of moss were not consumed.
I wish now to assemble the four study sites to discuss the progression of
----------~----·
251
---··~---·--·-·-··-·--~----~~----~-----···----·------·-·-·-·-----···---·--····-----·--·---·-··---
252
events as plants reinvaded the area.
Within a few weeks after the fire, we did find some Eriophorum regrowth,
but this was small and the soil surface began to dry out. Whenwe examined
the Sphagnum moss and upper peat layers, we found that buds of shrubby
plants looked as if they m~ght grow next year. Active layer depth was gener-
ally increased in the burned area. An exception to this was under moss
patches. Here the dead moss provided insulation and prevented permafrost
degradation.
One year after the fire we found a dramatically increased flowering of
Eriophorum vaginatum. Counts showed that there were three to 10 times
more seedheads on the burned area. Some of the other plants began to
emerge, but no seed appeared on the other plants. The active layer of the
burned sites was deeper than that of the controls. In the spring, the active
layer was 35 to 50 percent deeper and in the fall, 15 to 20 percent greater.
In other words, the length of the growing season had essentially increased
because of earlier spring permafrost melt.
By midgrowing season, most of the vascular species, including the slow-
growing ones, had begun to recover. At this point, we also noticed a number
of seedlings invading the burned area. Calamagrostis and Arctagrostis were
present, but only the Eriophorum seedlings showed high invasion rates (over
200/m2 ) in the summer. By the next spring, however, very few of the
seedlings had survived.
Since we were looking at four areas that had burned at different times, I
could piece together the vascular plant production of these areas. The
amount of regrowth was nearly 50 percent on the 1-year-old burned area as
compared with the control. On areas burned 2 years earlier, there was about
80-percent production compared with the control area. After 4 years, the
production of the burned area was 11 0 percent of the control. Most of this
latter increase was due to Calamagrostis and Arctagrostis. We are now trying
to determine why production recovers so fast. Analysis of plant tissue will
aid in determining if the nutrient status of the plants in the burned area is
much higher.
In summary, w~ have established that burns tend to be'light, at least in
this tundra vegetation type, because of the wet soil profile, and no vascular
species are completely eliminated by fire. Of course, lichens and mosses are
destroyed, and it will take a long time for them to reestablish. At
least some plants, such as cottongrass, have a vigorous seed production after
fire. This may be due to nutrients released by the fire, or it may be due to
translocation of food supplies within rhizomes so that the living portions
obtain more stored energy and can produce more seed. Also, there may be a
nutritional effect because of a warmer soil profile and a deeper active layer
~or a longer growing season.
The burned peaty surface is a very harsh site for seedling establishment,
and invading seedlings do not contribute much to production. Calamagrostis
and Arctagrostis, which are part of the original plant community, show the
greatest increase and spread after a fire. Other major components of the
community also show rapid recovery, and this makes the question of fire
frequency on tundra communities difficult to answer. If other tundra com-
munities regrow in similar fashion to the Eriophorum tussock community, a
burn may be difficult to detect in a very few years after a fire.
There has been considerable discussion regarding resource values and the Curtis V. McVee
fact that they are the determinant of the extent of fire control efforts so Bureau of ~
anything I might add would be redundant at this point. Research, as it Land Management
relates to the natural ecosystem, has also been most adequately discussed by Anchorage, Alaska
this group, with numerous innovative ideas being developed. Therefore, I
think my time here might be spent in discussion of some future aspects and
implications of fire control in Alaska.
One of the new legislative tools many of us will have to work with is the
Environmental Policy Act of 1969. The act is applicable to "major Federal
actions significantly affecting the quality of human environment." We have
been searching for a defmition of this statement, but this will not occur until
there has been some precedent established by the Council on Environmental
Quality and the courts.
We in fire control have always assumed our role was environmental protec-
tion. This will probably not be sufficient in the future, and we may have to
prove our case. I visualize there are two fronts on which we will be
questioned-so first let us question ourselves.
First, is fire detrimental to the environment? This may be the case in
terms of smoke pollution and the addition of particulate matter to the
earth's atmosphere. Fire does also result in degradation of wildlife habitat in
some instances and in acceleration of watershed deterioration. On the other
hand, it has always been part of natural ecosystems and its elimination may
not allow the dynamic ecosystem to properly function.
The second area will relate to our control practices and the question will
be, "Are the practices which you employ in controlling wildfires (physical
and chemical) affecting the quality of our environment?"
The ability of concerned groups and individuals to bring injunctive pro-
ceedings may force a discussion of these issues into the courts, and it will be
essential that we have the correct answers.
We in Bureau of Land Management feel that the time is past when public
lands can be indiscriminately transferred into private ownership or that
resources can be harvested without the benefit of comprehensive plans.
Alaska still has opportunities to analyze its options and to formulate land
and resource use policies and objectives as it proceeds to develop.
Economic development plans-which in this State are dependent on the
253
254
~----~~---~----~~~~
extraction and use of natural resources-must be founded on sound inven-
tories and analysis of resources. Alternatives should be carefully weighed and
choices calculated to preserve and enhance resources of the State and
Nation.
Built into such plans must be fire control aspects. There is opportunity to
plan growth in such a manner so as to minimize both the hazards and the
costs of fire control. We don't need a southern California situation with
people and property in a high risk area, although, to be sure, this is already
the case adjacent to Anchorage and to some extent immediately north of
Fairbanks.
We have a big job to do in creating an awareness of the costs of fire
control and in working to design land uses to reduce fire control cost and
risks. Local planners and zoning authorities can contribute to this effort and,
in many instances, hold the key. We know that scattered settlement and strip
settlement along the road and highway systems compound problems because
any dispersion of fire incidence creates attendant logistal problems.
Currently, the State of Alaska: bears the financial cost of controlling fires
on State and private lands. On land settlement claims where title has not
passed to the claimant, the Federal Government absorbs the cost. Under
recent legislation on disaster, the State is eligible for Federal funds when
serious fires occur.
I would like to suggest that maybe local governments and, more precisely,
property owners assume greater responsibility. I think this is particularly
applicable when related to the high man-caused incidences of fire in a State
which is as sparsely populated as Alaska.
The institution of a burning permit system as has been proposed by the
State and the strengthening of enforcement to eliminate promiscuous burn-
ing will reduce fires and probably costs, but the recognition by an individual
that carelessness will be reflected in a mill-levy increase may be much more
forceful.
I want to talk a bit more about planning. Currently our Anchorage district
has been working on a land and resource plan for an 11-million-acre area
encompassing the Wrangell Mountains. Part of this process is to define the
commercial forest areas, the recreation and scenic areas, wildlife use areas,
etc., to assure that resource use conflicts are identified. Choices will have to
be made. Out of this will come a multiple-use plan including a description of
fire control needs. For example: The wildlife biologists say that an annual
loss to fire of over 300 acres in the caribou wintering area south of the
Copper River will be detrimental. The recreation specialist will similarly
define management policies best suited for recreation management. These
are the kind of data the fire control planner needs to use as a basis for
designing a responsive program.
We can be assured of the fact there will be more people in Alaska, which
will result in more roads and greater dispersion of the population over the
-------~----
State with increasing demands on public lands and their resources. All of this
intensifies the fire control problems.
The symposium of the past 2 days has provided the opportunity for us to
be brought up~to-date on the state of knowledge of the effects of fire in the
northern environment. Although an excellent start has been made, it is also
quite apparent that the available knowledge on the subject is very limited.
We have only begun to penetrate what is a very complex ecological
relationship.
My specialty is wildlife ecology. It is apparent at this point that we in
animal ecology are not as far along in understanding fire ecological relation-
ships as are the plant ecologists. What we do know is in the form of gener-
alizations; we lack certain specific information which is essential for proper
management. Take, for example, moose, a species which has received con-
siderabie attention at the Kenai National Moose Range. We know quite a bit
about the relationship of moose to fires, but we really cannot say what is
most desirable in tenus of the relationship of fire to vegetation in view of
long-term benefits to moose. In the case of caribou, we also make generaliza-
tions. We know that lichens are a major source of the caribou's winter forage
and therefore we know, as Dr. Scotter has poirited out, that fire is quite
detrimental to caribou; but Dr. Scotter also alluded to the fact that under
some conditions fire may actually stimulate the irowth of lichens. There are
also indications from work in Scandinavia and the USSR that this may be
the case. It is somewhat like looking at fire in relationship to a white spruce
tree; obviously fire is detrimental to the individual tree but perhaps it is
essential for the well-being of the species. Perhaps fire is analogous to wolf
predation on caribou. For the individual caribou that's ta.ken by wolves there
is nothing beneficial about wolf predation, but wolves may be beneficial for
caribou as a population or a species, and fire rriay be beneficial for lichens
over a long period of time.
In the case of watetfowl in interior Alaska, we have observed in areas such
as the Yukon Flats, Minto Lakes, Tetlin Lakes, and Koyukuk Flats that the
productivity of these areas for waterfowl seems to be maintained by wide
extremes of nature: periodic flooding and periodic fires, Again, I am making
generalizations when we need very much inore specific information. Iri the
case of fur bearers, we can generalize and say that fires are most often
beneficial to fur bearers in that fires usually bring about an increase in
biomass productivity in a given area. We know that most fur bearers are near
the top of food chain pyramids and that if we broaden the base of these
pyramids, we increase the number of animals that can live near the top of
the pyramid.
There is not time to go into specifics about wildlife and fire and besides I
have already said we lack this type of information. So what I would like to
David R. Klein
Alaska Cooperative
Wildlife Research Unit
University of Alaska
College, Alaska
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256
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do in conclusion is to make a few generalizations about fire and resource
management and hope that they will stimulate discussion. It has already
been emphasized to us throughout the session that fire has multifaceted
effects on resources. These can be both positive and negative. It is not
necessary to enumerate the various resource values that are involved. Obvi-
ously we cannot let all fires burn, nor is it desirable to even attempt to put
out every fire. This means we have to make decisions-the question is who is
to make these decisions and on what basis. In many cases we have neither
the basic knowledge nor the technological competence to enable us to make
instantaneous decisions at the time of the fire. Obviously, priorities must be
established in advance. Any increase in our present knowledge will allow
more intelligent priorities to be established and more realistic fire decisions
to be made. Thus the need is very obvious for continued and expanded
research.
We also must understand and accept that biases are inherent in all of us. I
do not mean just the Smokey Bear complex (which a friend of mine refers to
that as "anthropomorphic ursininity"), but what I refer to are human com-
plexes which are more deeply ingrained. Perhaps most important is our
man-oriented shortsightedness. Man's time frame is certainly different from
that of nature. As scientists we talk about a 15-or perhaps a 25-year study as
being a long-term study. In the case of fire and ecology, we are dealing with
changes involving hundreds of years; obviously we are not speaking the same
language nor are we in the proper perspective to understand fire in an
ecological sense.
Another very important problem associated with man and his biases is in
realistically appreciating man's place in the environment. I think we all here
recognize that man is a part of the environment as well as being a product of
it. But he is unique among life, being the product of cultural as well as
biological evolution. As a result we are compelled, because of our past, to
think in terms of cultural as well as ecological values. Sometimes these are
not compatible. For example, there are very few of us here that could look
upon a newly burned climax white spruce stand and say that such a sight is
esthetically pleasing. This is a cultural bias. I'm not suggesting that we do
away with cultural biases; on the contrary, these are the very basis for much
of the richness in our lives. The important thing is that we must not confuse
cultural biases and cultural concepts with what are ecological truths. We
should not attempt to justify cultural concepts on ecological bases nor in the
name of ecology.
Perhaps I can simplify for you by reference to a hypothetical example.
What I am saying in terms of fire ecology is that in a given case if we so
highly value a climax spruce stand that we are unwilling to undergo the
short-term cultural losses associated with its burning then we should under-
stand the consequences and be prepared to meet them. In short, I think that
I am saying something that is akin to what motherhood used to be when
population increase was still fashionable; that is, that we should manage our
resources in knowledge rather than in ignorance.
Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Aprill3-14, 1971.
A Summation of
"FIRE IN THE NORTHERN
ENVIR 0 NMENT"
and a Suggestion for a
COOPERATIVE
ECOLOGICAL
EXPERIMENT STATION
This symposium on "Fire in the Northern Environment" has been an E. V. Komarek, Sr.
exciting exchange of ideas. Your chairman has asked that I present a Tall Timbers
"summation" and some "concluding remarks." The following summation Research Station
indicates clearly the need for more research of the proper kind for the Tallahassee, Florida
intelligent ecological management of fire. The symposium and the prepara-
tion of the summation has so stimulated me that for my concluding remarks,
I will discuss the formation of a cooperative ecological experiment station
for Alaska. The objective of such a station should be to find out ways and
means for man to work with nature, not to conquer or subdue her. The
purpose of such an endeavor should be to bridge the gap between science
and management. It is my earnest hope that the summation and the conclud-
ing remarks will spur you and other interested persons toward longtime
ecological experimentation and study, not only on fire but also on those
phases of ecology that are so badly needed for man to live in a harmonious
relationship with the unique Alaska environment.
The Summation
You have listened attentively to the speakers and have participated actively
in discussion for the past 2 days. Your presence is indicative of the interest in
the subject of fire in the northern environment of over 30 organizations: local,
State, and Federal government, private industry, and citizen. Over 100 partici-
pants have been gathered here, some from far distances, representing seven
States other than Alaska, and Canada. This kind of response certainly
emphasizes the widespread interest in Alaskan fire problems.
The sponsors of this symposium, the Alaska Forest Fire Council and the
Alaska Section of Society of American Foresters, have contributed much to
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258
the future welfare of this State and, in particular, to this subject, by bringing
all of us together to discuss, and even arg~e, the place of fire in the northern
environment. The expressed hopes of these organizations, as well as those of
our able chairman, Charles W. Slaughter, and his colleagues, Richard J.
Barney and Albert Comiskey, have been fulfilled. The stated purpose of this
symposium was
... to explore the many aspects of wildfire in the Alaskan Sub-
Arctic . . . to delineate and clarify some current questions and
opinions on wildfire ... [and] ... its relationship to the natural
environment, and to man's use of that environment-as well as to
consider some aspects of fire control in this region.
Thirty-one persons have expressed the~ ideas on fire in 26 papers; this
represents rnore technical papers on fire in Alaska than are listed in Larson's
(2) bibliography on fire in the far northern regions. The wide selection of
talks and the ensuing disc"!lssions have ·shown not only the broad scope of
this subject but also the competence of our chairman and his colleagues.
Ifoweyer, the papers, panels, and discussions' have revealed several imvortant
aspects anp paradoxes in relation to fire in the Alaskan environment that
must be explored. These are: ,
1. In interior Alaska, there is only a relatively small acreage that has
been designated by foresters as economic forest land in comparison
with an extremely large acreage classed as watershed, wildlife (game
and fish), and noncommercial forest land. This, for such a large region
in the United States, is a unique condition. Of the 350 million or
more acres in the interi,or basin, more than 230 million acres are
identified as tundra, marshes, bogs, rivers, and nonforest lands; about
80 million acres are classed as noncommercial forest land; and only
about 40 million acres are designated as economic forest land.
The primary usage and management therefore cannot be for the
commercial production of forest wood products. Thus, methods,
ideas, and philosophies that are pri,marily forest-oriented, either com-
mercially or ecologically, must only be used with the utmost caution
in the use, management, and development of most of this "!lnique
region.
2. Interior Alaska, because permafrost underlies much of the interior
basin, is ecologically different from most other regions. It is a unique
area, a "never-never land" for it is neither soil, nor water, nor ice, but
a variable mixture of all three. Methods of investigation and analysis
developed in other regions may not be valid under the conditions
existing in this area.
3. The interior basin, because it is a wet region but with a semiarid
climate, is a paradox. This situation in connection with the existence
of the underlying permafrost certainly creates unique ecological cir-
cumstances. The results from studies on fire effects and processes
conducted elsewhere may not always apply here. '
-----------~---~~~--~~~
4. Solar radiation in interior Alaska, because of the long sunlit days in
summer and virtually no sunlight in winter, creates conditions much
different from those in more temperate climates. An example ( 7) of
this is the following:
... relationship of soil temperature to forest cover in
northern regions contrasts with that of temperate regions
where frost penetration is greatest under nonforested areas
and far less or lacking under forests.
5. Several papers at this symposium have shown the very fragile nature
of the vegetative cover in the interior basin which if disturbed or
destroyed allows severe erosion to develop, resulting in accelerated
and permanent damage. Data have been produced indicating that fire-
fighting methods in this region must be adapted to the conditions
existing here and conducted in a manner different from those used in
other areas.
6. Interior Alaska is a natural lightning fire environment, and the plants
and animals are adjusted to fire. However, the effect of man's inter-
ference by either fire-exclusion or overburning is virtually uninvesti-
gated. Studies made in other regions cannot always be put to practical
use in this region because of the previously mentioned unique condi-
tions even though basic ecological principles apply.
7. Studies on the impact of fires on the habitat of large mammals show
the need for longtime studies in such a region as interior Alaska.
Investigations on the frequency, intensities, and kinds of fire and
their effect on the environment over a long period of time are non-
existent. An example of the differences that occur is the following. In
recent years, two excellent investigations into the life history and
habitat of the caribou have been made; one on the barren-ground
caribou in the Northwest Territories by Scotter (4, 5) and another by
Skoog ( 6) on the Alaskan caribou in Alaska. Some of the differences
that arise are well brought out by Scotter (5) as follows:
Skoog (1968) concluded that range destruction by fire
had little influence on known caribou populations fluctua-
tions in Alaska. He stated that losses of range due to fires
were greatly mitigated because caribou were not depend~
ent for forage upon lichen growths in spruce forests.
Forages in other communities such as tundra, alpine
meadows, and other areas could be utilized. He considered
doubtful that fires had much influence on fluctuations in
caribou numbers in Alaska.
There is a marked contrast, however, between much of
the winter range used by barren-ground caribou in Canada
and the winter range used by caribou in Alaska. If a winter
range burned in the relatively flat taiga of northern Canada
it might cause caribou to move miles in search of food; in
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Alaska, the caribou might merely have to move a short
distance up the mountain side into the alpine region to find
lichens and other forage to meet their nutrient require-
ments. (italics Komarek's)
A review of these two studies shows that they are concerned with
two entirely different conditions. Likewise, we are dealing with two
different subspecies of caribou, the barren-ground caribou (Rangifer
tarandus groenlandicus) and the Alaska caribou (Rangifer tarandus
granti). I (1) have mentioned that the wide ranging migrations, partic-
ularly of the barren-ground caribou, might well be, at least in part, an
"adaptation" to widespread fires. Fires certainly play a large part in
the movements and migrations of some of the large ungulates in
Africa.
8. We have listened to excellent papers on the effect of fires on the
quality of the water environment that highlight the need for long-
term investigations in the interior basin. Little appears to be known
about nutrient recycling by fire into the streams and lakes of this
region. In southeast States, a common practice based on extensive
investigations is the fertilizing of fish ponds with such nutrients as
potash, phosphate, and lime. What kind of fires, how frequent, etc.,
produce the same result in nature? Studies of watersheds where fire
has been excluded for a long period by man and then burned by
wildfire under drastic climatic conditions are not investigations of
natural events.
9. No investigations of any serious nature have been made on the effect
of fires upon the habitats of the waterfowl that frequent interior
Alaska. What kind of fires, and how frequent, produce the best condi-
tions for waterfowl? It is a regular practice on many waterfowl
refuges from southern Canada to the Gulf of Mexico to use controlled
burning in the successful management of the habitat for many species
of waterfowl. Recent studies at the Northern Prairie Research Center
at Jamestown, North Dakota, show the intricate relationships of fire
not only with food production but with predation on nesting grounds
as well. Under certain vegetative conditions, predation on duck nests
is exceedingly high. This predation is lowered extensively by properly
controlled burning.
10. The study and use of controlled or prescribed burning, except as .it
pertains to slash bt!rning from clearcutting, is conspicuous by its
absence not only in this symposium, but in the literature. Common
sense would dictate its proper use if for no other reason than hazard
control and safeguarding homes, installations, and economic forests.
Interior Alaska is a natural fire environment and thus fire is part of
the wildlife habitat. However, with the increasing development of this
region, it may become necessary for the use of control burning on an
extensive scale. Large regions in both Africa and Australia are burned
regularly: by ground application and for game or other wildlife
purposes in the former; by aerial application for silvicultural and
wildlife purposes in the latter. Aerial application of controlled burn-
ing might well be applicable to interior Alaska.
The Suggestion
A COOPERATIVE ECOLOGICAL EXPERIMENT STATION
FOR ALASKA
Alaska. will grow-and progress-as have all the other States,--ror Alaska-ns
have no desire to remain a pioneer or wilderness State, at least not entirely.
Its population will increase, its cities will enlarge and new urban areas devel-
op, and its industries will not only grow but multiply as well. Thus the
question is, how best can this development and growth be guided with the
least disruption of the natural environment and for man's own welfare as
well?
The inhabitants of the lower 48 States are in no position to single out
Alaskan problems when their own environments are rapidly being destroyed
by burgeoning expansion of urban, industrial, recreational, and highway
developments. Alaskan development, like its research and problems, must in
the main be solved by its own peoples. As pointed out in the summation,
this is particularly true for Alaska because of the uniqueness of its natural
environment. However, the lower States can serve as an example, for both
good or bad as the case may be, to the future direction and guidance of
Alaska.
One of the "good" examples from the lower States which has already
been introduced is the State Agricultural Experiment Station at Palmer,
Alaska. The creation and development of the system of State Agricultural
Experiment Stations in the late 1800's has materially assisted the Nation in
becoming the leading food producing country. This agricultural productive-
ness and technology was created by experimentation by both the agricultural
stations and the farmers as well. This agricultural foundation, in turn, made
it possible for the rapid industrialization of the Nation. The problems of
pollution of our environment today are the result of rapid technology and
consequent urban growth without guidance or direction by industrial or
urban experiment stations. It is time we enlarge upon the time-tested experi-
ment station approach and apply it to the ecological management of the
'world in which we live, instead of limiting it only to agricultural production.
It is with this idea in mind that I suggest to you the creation and develop-
ment of a cooperative ecological experiment station for interior Alaska
modeled in many .respects after the successful pattern of the agricultural
experiment stations.
Purpose.-The purpose of an Alaskan cooperative ecological experiment
station should be to seek and develop facts and other information by scien-
tific experimentation on the relationship of man and his objectives to
Alaska's unique natural environment. There is a great need for facts, not
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262
optmons, on how to successfully manage, direct, and conduct, as well as
cope with, the growth and industrial expansion in Alaska. The objective of
the Station should not be to conquer nature but to find out ways and means
for man to work with nature. The purpose should be to bridge the gap
between science and management.
Science and management.-This objective is difficult to reach because of
certain inherent differences between science and management. Science is the
accumulation not only of facts, however, but also of the understanding of
the principles upon which our natural environment operates. Science is not
an attack on a problem but a search for an understanding of the ecological
complexities and a realization of the variations in nature. Management, on
the other hand, is not a science but an art, for it is the "judicious use of
means to accomplish an end." Facts and information from science must be
taken and weighed in comparison with the objectives of management. This
ultimately means that the solution is reached by compromise. Much of the
argument between environmentalists and industry today is because facts are
few and there is little understanding of the ecological diversity and com-
plexity in nature.
I have chosen the title Cooperative Ecological Experiment Station with
care and each word in it designates an important function of such an
endeavor. These words have been placed in that juxtaposition for semantic's
sake but in importance they should be emphasized as experiment, coopera-
tive, ecological, and station, and I will discuss them in that order.
Experiment.-Let me make clear to you at the onset that I consider the
approach and methodology of an ecological experiment station as quite
different from that of the usual biological station, ecological institute, or
research center. An experiment station is "where experiments are tried,
studies of a practical value made, and information disseminated" (3). An
experiment is an "act or operation undertaken in order to discover some
unknown principle or effect, or to test, establish, or illustrate some suggested
or known truth" (3). To experiment is the "action of trying or testing; the
conducting of a test or a series of tests" (3). Thus, the basic purpose of an
ecological experiment station must be the idea of manipulation, of testing,
of experimentation, not just the observance or censusing of plants or animals
and their behavior, or the study of the life history of an organism. To
illustrate my meaning to you, let me give you the following example.
An ecological experiment station not only would study the effects of fire
on plants, animals, soils, etc., caused by a wildfire but would in addition
set up sizable plots which would be studied in their entirety to be reasonably
positive that they were comparable. These then would be burned at various
intervals such as annually, every third year, every fifth year, and so on. Some
plots would be used as controls and fire would be rigidly excluded; others
would be treated or manipulated with severe fire, or cool or feeble fires; and
still others would be mowed, bulldozed, herbicided, and bush-and-tree-
chopped in a manner comparable to the operation now going on at the
Russian River Burn. I cannot help but wonder at the effect of the latter type
of "reconstruction" at the Kenai Wildlife Refuge on the soils, vegetations,
and animal life for I know of no parallel or experimentation or study of such
a vast operation in the far north. The experimental plots should be main-
tained for a long period of time-over 100 years.
At the Tall Timbers Research Station, we have a series of 84 "Stoddard"
fire plots under various frequencies of fire along with plots where we hope
fire will be excluded for over 1 00 years. Although these plots are only 12
years old, they-are -already being utilized for-studies not only by-ourstaff
but by other investigators because they have a known history. The ecologist,
if he wishes to understand the env~ronment in which man lives, must test; he
must manipulate and not only observe.
Cooperative.-The operation of an ecological experiment station must, if
it is to realize its objectives, be cooperative because of the complexities in
nature. Close cooperation must be maintained between specialists, scientists
in other fields of science, as well as with agencies, organizations, institutes,
and the public and industry. No such station could develop a large enough
staff to operate alone. The State agricultural experiment stations have
developed very valuable and extensive cooperative efforts with public and
private agencies and with farm groups and farm industries as well.
The close cooperation of a State cooperative ecological experiment station
in Alaska with Federal agencies would be essential because of the large
acreages in Federal ownership. Close liaison would be necessary with such
valuable but more or less specialized agencies such as the Institute of North-
ern Forestry, Arctic Institute of North America, Cold Regions Research and
Engineering Laboratory (CRREL), and the many research and teaching units
of the University of Alaska. However, it should be made clear that an
ecological experiment station is not a training ground for graduate students;
rather, its primary purpose is longtime experimentation directed by a trained
staff whose entire time would be taken up with research.
Cooperative effort with private and public industry must be achieved, for
the purpose of such a station is to furnish facts and information so that man
and his technology can live in harmony with the natural environment. The
agricultural experiment stations have achieved this close cooperation with
both the public and industry in a mo~t remarkable manner. An ecological
experiment station. such as I visualize will fall short of its goal if all it does is
accumulate information that is not usable to man and his tec~nology.
Ecological.-ln many respects an ecological experiment station is quite
different from its counterpart, the agricultural experiment station. The lat-
ter's primary objective is increased economic food and fiber production,
whereas the former's goal is to seek ways and means for man an<;l his pursuits
to live in harmony with his natural envirop.ment. Ecology deals with the
mutual relations between organisms and their environment, and man is part
of this affiliation. An ecological experiment station strives to make this
relationship a mutual alliance, not a discordant conflict. The habitat of man
f
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264
includes all of the natural surroundings and influences that affect the
development of living things, and it is to mankind's longtime benefit to live
in harmony with these. surroundings and influences. To accomplish such a
harmonious relationship, man must experiment, must manipulate on an
experimental basis, before undertaking large projects that may inhibit or
destroy such a beneficial condition.
Station.-An Alaskan cooperative ecological experiment station must have
permanently owned land upon which to conduct longtime experiments. It
must not be swayed from its main purposes by utilizing lands that are
already set aside for other uses, for its goal is not increased economic pro-
duction of food and fiber although there will probably be useful "spin-offs"
from ecological experiments useful to such production. The station should
be located on land that is underlain with permafrost so that this condition
can be observed regularly by the staff. Sub-or field-stations can be located in
areas of semipermanent permafrost conditions as well as in permafrostfree
regions. It should be apparent that sufficient land must be set aside for
experimental investigations because longtime experiments will of necessity
occupy much land for a long period. The station by cooperative agreements
can also conduct some experimental studies on lands held by other agencies
and for other purposes, but the station's primary objective should always be
in mind: man's harmonious relationship with nature and how best to achieve
this desirable state. The station for many reasons should be located near
Fairbanks, thus easily accessible not only to the city but to the many
agencies, institutes, and the university as well.
Staff.-Land, buildings, equipment, or ideas will not achieve by themselves
the alliance with nature we wish. Of greatest importance to an ecological
experiment station must be a competent staff with an ecological outlook. It
will be difficult to find imaginative and creative scientists, particularly
among ecologists, who have what is called a practical viewpoint. Unfortu-
nately, it has been the custom in certain scientific circles, particularly
academic, to frown upon or look down upon, investigations that have an
applied or practical application. This appears to have been especially true
among natural scientists and ecologists. This attitude of mind has usually
been coupled with the need for more and more "basic research," but I fear
that at least at times the scientist has only done what he wanted to do.
Likewise in such research it is difficult to tell whether or not anything is
accomplished regardless of how much money is spent. A review of current
literature and dissertations in the natural science or ecological field shows a
lack of appreciation for experimental methods on the ground over a long
period of years, particularly in the form of replicated plots, controls, and
various methods of manipulation of the vegetative cover or of the animal
populations. Thus a staff for an ecological research station must be chosen
with care for the prime objective of the investigations is information to be
used in the wise management of this unique arctic environment. If practical
results are not forthcoming, the policies must be reviewed and altered to
meet this objective. The development and use by man of the arctic regions
--~---~--------·_!__ _________ , ______ ~----
will not be stayed. Therefore, the early establishment of a cooperative
ecological experiment station for Alaska is imperative for guidance in this
development and usc.
Literature Cited
1. Komarek, E. V. 1965. Fire ecology-grasslands and man. Fourth Tall
Timbers Fire Ecol. Conf. Proc., p. 169-220.
2. Larson, S. M. 1969. Fire in far northern regions, a bibliography. U.S.
Dep. Interior, Dep. Libr., Washington, D.C.
3. Neilson, W. A., T. A. Knott, and P. W .. Carhart (eds.). 1946. Webster's
new international dictionary of the English language. Springfield, Mass.:
G. & C. Merriam Co., Publ.
4. Scotter, G. W. 1964. Effects of forest fires on winter range of barren-
ground caribou in northern Saskatchewan. Can. Wildlife Manage. Bull.
Ser. 1, No. 18, p. 1-111.
5. . 1970. Wildfire in relation to the habitat of barren-ground
caribou in the taiga of northern Canada. Tenth Tall Timbers Fire Ecol.
Conf. Proc., p. 85-105.
6. Skoog, R. 0. 1968. Ecology of the caribou (Rangifer tarandus granti) in
Alaska. 699 p. Unpubl. Ph.D. thesis, Univ. Calif., Berkeley.
7. Viereck, L. A. 1970. Forest succession and soil development adjacent to
the Chena River in interior Alaska. Arctic & Alpine Res. 2(1): 1-26.
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Proceedings-Fire in the Northern Environment-A Symposium.
College (Fairbanks), Alaska-Apri113-14, 1971.
0 Attendance list
Adams, William H. . . . . . . . . . . . . . . . . Bureau of Land Management
Post Office Box 941
Eagle River, Alaska 99577
Albert, Thomas W. . . . . . . .. . . . . . . . . . Bureau of Land Management
4416 Airport Way
Fairbanks, Alaska 99701
Atkins, Alfred S. . . . . . . . . . . . . . . . . . Post Fire Department
Ft. Wainwright, Alaska 99703
Barney, Richard J ................. U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 9970 1
Bartonek, James C ................. Bureau of Sport Fisheries
and Wildlife
1412 Airport Way
Fairbanks, Alaska 99701
Beckwith, Roy C .................. U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 99701
Benson, Victor R. . . . . . . . . . . . . . . . . . Fairbanks Fire Department
310 18th Avenue
Fairbanks, Alaska 99701
Berglund, Erwin R ................. Department of Land Resources
University of Alaska
College, Alaska 99701
Berry, Elizabeth M ................ U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 99701
Betts, Robert C. . . . . . . . . . . . . . . . . . . Bureau of Land Management
4416 Airport Way
Fairbanks, Alaska 99701
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267
268
Bigler, Stuart G ................... NOAA-National Weather Service
2526 Arlington Drive
Anchorage, Alaska 99503
Bishop, Maj. Henry J ............... Alaskan Command
Headquarters ALCOM
Elmendorf AFB, Alaska 99506
Bolstad, Roger A. . . . . . . . . . . . . . . . . . Bureauof Land Management
Post Office Box 1150
Fairbanks, Alaska 9970 I
Clithero, Robert A ................ Bureau of Land Management
Pipeline Division
702 24th Avenue
Fairbanks, Alaska 9970 I
Cohen, DanK .................... Chief, Fire Protection
5236 East Arctic
Eielson AFB, Alaska 99702
Comiskey, Albert ................. National Weather Service
1649 Birchwood Street
Anchorage, Alaska 99504
Cooper, Horace G ................. Arizona Agrochemical Corporation
13767 NE San Rafael
Portland, Oregon 97230
Costello, Paul C ................... Cold Regions Research and
Engineering Laboratory
Post Office Box 160 I
Fairbanks, Alaska 9970 I
Couture, Wayne D. . . . . . . . . . . . . . . . . University of Alaska (student)
506 Bartlett
College, Alaska 99701
Cronk, Allen R. . . . . . . . . . . . . . . . . . . Bureau of Land Management
I Mile McGrath Road
Fairbanks, Alaska 99701
Dean, Frederick C. . . . . . . . . . . . . . . . . Department Wildlife Management
University of Alaska
College, Alaska 9970 I
Dean, Thomas . . . . . . . . . . . . . . . . . . . Bureau of Land Management
Post Office Box 5-644
College; Alaska 99701
DeLeonardis, Sal . . . . . . . . . . . . . . . . . Bureau of Land Management
555 Cordova Street
Anchorage, Alaska 99501
Deneke, Fred . . . . . . . . . . . . . . . . . . . . Cold Regions Research and
Engineering Laboratory
Post Office Box 160 1
Fairbanks, Alaska 99701
Dooley, Dennis ................... University of Alaska (student)
General Delivery
College, Alaska 99701
Douglas, William J ................. Bureau of Reclamation
7037 South Platte Canyon Road
Littleton, Colorado 80123
Elliott, Gail E. . . . . . . . . . . . . . . . . . . . Bureau of Land Management
491 Sprucewood Road
Fairbanks, Alaska 99701
Emmert, Reginald A. . . . . . . . . . . . . . . University of Alaska
Post Office Box 5-329
College, Alaska 99701
Freel, Richard D. . . . . . . . . . . . . . . . . . Bureau of Land Management
General Delivery
College, Alaska 99701
Grigel, Joe E ..................... Canadian Forestry Service
Prairies Region
Edmonton, Alberta
Grundy, J. Scott .................. Alaska Department of Fish
and Game
5¥2 Mile Steese Highway
Fairbanks, Alaska 99701
Hakala, John B ................... Bureau of Sport Fisheries
and Wildlife
Post Office Box 241
Kenai, Alaska 99611
' §
L
269
270
Harris, Robert W .................. U.S. Forest Service
Pacific Northwest Forest and
Range Experiment Station
Post Office Box 3141
Portland, Oregon 97208
Randleman, Avrom R. ............. Monsanto Company
800 North Lindbergh
St. Louis, Missouri 63166
Hansen, Royal G. . . . . . . . . . . . . . . . . . Alaska Division of Lands
~ Mile Laurance Road
Fairbanks, Alaska 99701
Harrison, Jose R. . . . . . . . . . . . . . . . . . Alyeska Pipeline Service Company
Post Office Box 131 0
Fairbanks, Alaska 99701
Harry, Raymond C ................ U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 99701
Hegg, Karl M ..................... U.S. Forest Service
Institute of Northern Forestry
R. R. 2, Box 1207
Juneau, Alaska 99801
Heinselman, Miron L. . . . . . . . . . . . . . . U.S. Forest Service
North Central Forest Experiment
Station
Powell Avenue
St. Paul, Minnesota 55101
Helmers, Austin E. . . . . . . . . . . . . . . . . U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 99701
Hendrie, Ronald A. . .............. State Fire Marshal's Office
1616 Cushman Street
Fairbanks, Alaska 99701
Hoffman, Joe E. . . . . . . . . . . . . . . . . . . Institute of Social, Economic
and Government Research
University of Alaska
College, Alaska 99701
I
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Hollett, George K. . . . . . . . . . . . . . . . . State Division of Lands
229 Bentley Drive East
Fairbanks, Alaska 99701
Hovland, Dwight R. . . . . . . . . . . . . . . . Bureau of Land Management
110 East 11th Avenue
Anchorage, Alaska 99501
Janke, Robert A .................. Michigan Tech. University
Bioscience Department-
Houghton, Michigan 49931
Jayaweera, K. Oswald . . . . . . . . . . . . . . Geophysical Institute
University of Alaska
College, Alaska 99701
Jeglum, Carl P. . . . . . . . . . . . . . . . . . . . Bureau of Land Management
1 707 Jack Street
Fairbanks, Alaska 99701
Kiil, David A ..................... Canadian Forestry Service
5320 122 Street
Edmonton, Alberta
Klein, David R. . . . . . . . . . . . . . . . . . . . Alaska Cooperative Wildlife
Research Unit
University of Alaska
College, Alaska 99701
Komarek, Ed. V., Sr., and Betty ...... Tall Timbers Research Station
Route 1, Post Office "6ox 11 0
Tallahassee, Florida 32301
Krumm, Robert C. . . . . . . . . . . . . . . . . Bureau of Land Management
1 028 Gilmore
Fairbanks, Alaska 99701
Larsen, Robert D. . . . . . . . . . . . . . . . . . Bureau of Land Management
Post Office Box 146 2
Fairbanks, Alaska 99701
Larson, Charles E. . . . . . . . . . . . . . . . . Bureau of Land Management
4416 Airport Road
Fairbanks, Alaska 99701
Lines, Leon L. ................... British Petroleum of Alaska
Post Office Box 1423
Star Route A
Anchorage, Alaska 99502
F-
271
272
Lockhart, James R. . .............. Federal Aviation Administration
632 6th Avenue
Anchorage, Alaska 99501
Lotspeich, Fred B. . . . . . . . . . . . . . . . . Alaska Water Laboratory
University of Alaska
College, Alaska 9970 1
McVee, Curtis V .................. Bureau of Land Management
555-Cordova Street
Anchorage, Alaska 99501
Mehl, Mel S. . . . . . . . . . . . . . . . . . . . . . Bureau of Land Management
Post Office Box 1150
Fairbanks, Alaska 99701
Miller, Ivan ...................... National Park Service
Mt. McKinley National Park
McKinley Park, Alaska 99755
Moore, Walter J. . . . . . . . . . . . . . . . . . . Mackenzie Forest Service
Post Office Box 322
Fort Smith, Northwest Territory
Morgan, David J .................. Yukon Forest Service
Post Office Box 3206
Whitehorse, Yukon Territory
Mueller, Ernst W .................. Alaska Water Laboratory
University of Alaska
College, Alaska 99701
Noonan, Laraine. . . . . . . . . . . . . . . . . . University of Alaska
Forest Soils Department
College, Alaska 99701
Noste, Nonan V ................... U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 99701
Peacock, Clyde E. . . . . . . . . . . . . . . . . . U.S. Forest Service
1575 Evergreen Avenue
Juneau, Alaska 99801
Percival, Roy M. . . . . . . . . . . . . . . . . . . Bureau of Land Management
4046 Birch Lane
Fairbanks, Alaska 99701
Prasil, Richard J. . . . . . . . . . . . . . . . . . National Park Service
Post Office Box 2252
Anchorage, Alaska 99501
Quirk, Bill . . . . . . . . . . . . . . . . . . . . . . University of Alaska
1215 Hess Avenue
College, Alaska 9970 I
Richardson, James H ............... Bureau of Land Management
555 Cordova Street
Anchorage, Alaska 99501
Roberts, Arthur M ................. Western Forestry and
Conservation Association
American Bank Building
Portland, Oregon 97208
Robertson, William C .............. Bureau of Land Management
4416 Airport Road
Fairbanks, Alaska 9970 I
Sala, Dan L. ..................... National Weather Service
Post Office Box 3027
Fairbanks, Alaska 99701
Scatter, George W ................. Canadian Wildlife Service
515 Centennial Building
Edmonton 15, Alberta
Seetles, Raymond L. . . . . . . . . . . . . . . Alaska Division of Lands
2307 Lincoln Avenue
Anchorage, Alaska 99504
Shepherd, Peter E. K. . . . . . . . . . . . . . . Alaska Department of Fish
and Game, Habitat Section
Post Office Box 8454
Mt. View, Alaska 99504
Slaughter, Charles W ............... Cold Regions Research and
Engineering Laboratory
Post Office Box 160 1
Fairbanks, Alaska 99701
Stephenson, John ................. Bureau of Land Management
Wildwood #21 - 1 Mile
McGrath Road
Fairbanks, Alaska 99701
~-
273
274
Stonorov, Tina ................... Rand M Engineering and
Geological Consultants
Post Office Box 2630
Fairbanks, Alaska 99701
Stover, John C .................... Alyeska Pipeline Service Company
2101 Dahl Lane
Anchorage, Alaska 99503
. Strandberg, Jim .................. Rand M Engineering and
Geological Consultants
Post Office Box 2630
Fairbanks, Alaska 99701
Striffler, W. D .................... Colorado State University
1201 Lory
Ft. Collins, Colorado 80521
Swift, Harry L. ................... National Weather Service
Grammas Building Wll5X2
8060 13th Street
Silver Spring, Maryland 20910
Sykes, Dwane J. . . . . . . . . . . . . . . . . . . Department of Land Resources
University of Alaska
College, Alaska 99701
Sylvester, Roger A ................. Bureau of Indian Affairs
Post Office Box 1215, R.R. 2
Juneau, Alaska 99801
Tackle, David . . . . . . . . . . . . . . . . . . . . U.S. Forest Service
Pacific Northwest Forest and
Range Experiment Station
Post Office Box 3141
Portland, Oregon 97208
Tank, Robert E. . . . . . . . . . . . . . . . . . . Bureau of Land Management
833 North Bunn
Anchorage, Alaska 99504
Timmons, Jerry .................. Bureau of Land Management
Delta Junction, Alaska 99737
Trigg, William M .................. National Weather Service
840 Fourth Street
Fairbanks, Alaska 99701
Triplett, Wallace,Jr. . .............. Assistant Fire Chief
Eielson Air Force Base
1860 2nd Avenue
Fairbanks, Alaska 99701
Wahl, H. E ....................... Canadian Weather Service
Department of Transport
Whitehorse, Yukon Territory
Webber, Robert W ................. Bureau of Land Management
4416 Airport Way
Fairbanks, Alaska 99701
Weber, G. P. National Weather Service
1565 Sunrise Drive
Anchorage, Alaska 99504
Weeden, Robert B. . . . . . . . . . . . . . . . . University of Alaska
Post Office Box 5-425
College, Alaska 99701
Wein, Ross W ..................... University of Alberta
Botany Department
Edmonton, Alberta
Wright, Kenneth H. U.S. Forest Service
Pacific Northwest Forest and
Range Experiment Station
Post Office Box 3141
Portland, Oregon 97208
Van Cleve, Keith ................. Forest Soils Laboratory
University of Alaska
College, Alaska 99701
Zasada, John C. . . . . . . . . . . . . . . . . . . U.S. Forest Service
Forestry Sciences Laboratory
College, Alaska 99701
* U.S. G. P. 0. 795·239
275
L
r---------------------·---------------------------------------------------------------~--r·----------------------------~---------------------------------------------------------~
Slaughter, C. W., Richard J. Barney, G. M. Hansen (eds.).
1971. Fire in the northern environment-a symposium.
Pacific Northwest Forest and Range Experiment Sta-
tion, 275 p., illus. Portland, Oregon.
The proceedings includes papers exploring many aspects of
wildfire in the Alaskan subarctic, its relationship to natural
environment, and its control.
Keywords: Fire control, environment, Alaska.
Slaughter, C. W., Richard J. Barney, G. M. Hansen (eds.).
1971. Fire in the northern environment-a symposium.
Pacific Northwest Forest and Range Experiment Sta-
tion, 275 p., illus. Portland, Oregon.
The proceedings includes papers exploring many aspects of
wildfire in the Alaskan subarctic, its relationship to natural
environment, and its control.
Keywords: Fire control, environment, Alaska.
----------------------------------------------------·------------------------------------··---------------------------------------~-------------------------~~----------------------~
Slaughter, C. W., Richard J. Barney, G. M. Hansen (eds.).
1971. Fire in the northern environment_:a symposium.
Pacific Northwest Forest and Range Experiment Sta-
tion, 275 p., illus. Portland, Oregon.
The proceedings includes papers exploring many aspects of
wildfire in the Alaskan subarctic, its relationship to natural
environment, and its control.
Keywords: Fire control, environment, Alaska.
Slaughter, C. W., Richard J. Barney, G. M. Hansen (eds.).
1971. Fire in the·· northern environment-a symposium.
Pacific Northwest Forest and Range Experiment Sta-
tion, 275 p., illus. Portland, Oregon.
The proceedings includes papers exploring many aspects of
wildfire in the Alaskan subarctic, its relationship to natural
environment, and its control.
Keywords: Fire control, environment, Alaska.
The mission of the PACIFIC NORTHWEST FOREST
AND RANGE EXPERIMENT STATION is to provide the
knowledge, technology, and alternatives for present and
future protection, management, and use of forest, range, and
related environments.
Within this overall mission,,• the Station conducts and
stimulates research to facilitate and to accelerate progress
toward the following goals:
1. Providing safe and efficient technology for inventory,
protection, and use of resources.
2. Development and evaluation of alternative methods
and levels of resource management.
3. Achievement of optimum sustained resource produc-
tivity consistent with maintaining a high quality forest
environment.
The area of research encompasses Oregon, Washington,
Alaska, and, in some cases, California, Hawaii, the Western
States, and the Nation. Results of the research will be made
available promptly. Project headquarters are at:
College, Alaska Portland, Oregon
Juneau, Alaska. Roseburg; .. Oregon
Bend, Oregon Olympia, Washington
Corvallis, Oregon Seattle; Washington
La Grande, Oregon Wena~chee, Washington
1 ' , ~\
~..mP.'A:flrtmF!nt of Agriculture
is dedicated to the P/l~l~l~~LJ;gyJ'!~fJli}j~s,e management of the
Nation's forest of wood, water,
forage, wildlife, forestry research,
cooperation with owners, and
management of t oe Grasslands, it
strives -as provide increasingly