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HomeMy WebLinkAboutAPA2484.... .::" )-. ' }// _..'.., 1 \ ,.A, ('") .. // 'fe.! ~ 1 TWO YEAR RESPONSE OF WOODY PLANTS TO LETOURNEAU TREE CR~SH~RS ON THE KE~AI N:'l.T I G~J~L t .• ~r!f1s~ '\·st~ .. -1~r:·-r . '.J•J ..... '• 1 ..JL.... f John l. Oldemeyer U. S. Fish and Wildlife Service Denver Wildl ife Research Center Kenai, Alaska 1~13 1 0'30'-/ -- MOose are creatures of secondary plant succession; they thri~e after dis turbance; _-_One of:_ the: most important dis turbances i s fi re, and chânges in moose populations after fire have been well documented. In t·1ichigan (Krefting 1974) and Alaska (Lutz 1956} and Spencer and ·Hakala (1964) moose populations increased and remained higher for 10-20 yecrs after fire before declining due to changes in vegetative composition and to hardwood saplings grmving beyond normal browsing height. logg~ng is another important disturbance factor that influences moose populations. Studies in Canada (Telfer 1972) and Minnesota (Peek et al. 1976) reported moose populations respond to changes after 1ogging in a manner simi- lJr to changes after fire. However, in calder regions, one might expect the ' response of vegetation after logging to be somewhat faster than after fire be- cause tnere may be less destruction to the total plant co1m1unity and to the upper soil layers. The Kenai National Moose Range on the Kenai Peninsula, Alaska has a fire nistory recorded back to the mid l800's. Hajor fires this century occurred in 1926, 1947, and 1969. t>"A)ose populations reached high leve1s in the mid-1930's and the late 1960's in response to the two earlier fires. The population is presently 3,500-4,500 moose, about one half the 1971 1eve1. *Paper presented at th'ê" 14th North American Moose Conference and Workshop, Halifax, Nova Scotia, April 24-27, 1978. ARLIS Alaska Resources Library & InfonnàtiOn Servtces Anchorage, Alaska .... ~<il 'j '~1 ! ~ 0 co "' M ex:> M 0 0 0 1.0 ,-~ -; ·, .... ·~ / METHOOS In 1975 and-1976 experimental programs to create ~aJ~r plant jjstur~ance for improving browse composition were conducted on the Kenai .. ~ ~~,., Nùtional Moose Range in a part of t~'le 1947 Burn and interspersed ur:~()rnt::d for- est. From January-March 1975 Moose Range staff used Le7o1Jrneau tree crushers to crush vegetation on about 460 ha in the Wi1low lake area in the northern part of the -Moose Range,_ -.:rhe project was designed to crush a dou')nut-::,haoed area, with plans to burn the 156 ha doughnut hale the next spring. Unfortu- nately, it has been either too wet or tao dry to burn successfully, and this phase has not yet been completed. Our objective vJas tonstudy the vegetationa1 changes resulting from crushing and fire with the hope that white ana-black .. ., spruce (Picea glauca and f_. mariana) density I•Jou1d be reduced while t:lensity and ri ch ness ôf ha rd wood brov1se s pee i es wou 1 d be i ne re,J s ed . From January-March 1976 approximate1y 520 ha were c1~ushed in the 1947 Burn south of the Kenai Moose Research Center (MRC) and about 8 km from the ~:i 11 0\·t Lake area. The stands samp1ed in the two areas had simi1ar woody species compositi-on (Tables 1 & 2). Mature timber in .the area of the white spruce-paper birch (Betula papvrifera) -aspen (Populus tremuloides) type and regrowth of paper birch ané black spl~uce. The MRC ·area, howe•Jer, is a more general black s~ruce ty:;e as shawn by stands 5-21 and 5-24 in Tab 1 e 2. Ten sample stands were selected atWi11mrlake to represent the variety of vegetaticin types in that area. Seven of the nine sample stands at MRC had been part of an ongoing study at MRC (Oldemeyer 1975) and had been se1ected because ~ of their similarity to stand \;rithin the MRC. The other two stands \-lere selected M ,.. M , in the wide belt of black spruce that occurs r south of the MRC. ARLIS Alaska Resources Library & Informatton Servtces Anchorage, Alaska ' t ·~, 1 .. '. C-J-I.::;à.' 3 -cc-; <.... .._.,. tf qLQ':y;JL~ ln each stand, woody plant density was samplcd in 25, 1 x 5 randomly 1oc3ted quadrats. ~ 2 x 5 Guadrat was nested wi~~in eac1 larger Jua~r~~ and caver of a11 plants shorter than 40 c111 estimated using modified classes of tii.e method described by Daubenmire (1959). :'\. soil pit was,. duttJp1 each stand and depth to the A, 8, and c·harizons measured. A sail sample was r~- moved from the A and 8 horizons for determination of pH and of rock, sand, silt and clay. Vegetation surveys were conducted before and two growing -seasons after crushing, except that the 2 x 5 d~ survey of caver was not con- ducted prior to crushing at MRC. {;, RESULTS AND DISCUSSION Black ~ruee. Black spruce occurred in five stands at ~Jillm·1 Lake and in eight stands at iv1RC. Effects of crushing \·lere similar in both areas vlith 77.5-and 83.1 percent reduction in density, respectively, and reduction in height from about iSO cm to 70 cm. The reduction in black spruce der.sity and height bene- ·fit browse species because of reduced competition fer water, nutrients, and sun-. 1ight. Paper 13irch. In all mature stands {C-1, C-3, C-7, C-8, and 5-06) paper bircil cens ity v1as 1 ov1 be fore crushi ng. After crus hi ng. bi rch dens ity i ncreased in the mature stands Jt Willo\'1 Lake and decreased at ~1RC. Density increased or re1:1ained the same in the six regrowth stands ~t \·lillovt Lake but decreasêd sig- nifiçant1y in six of eight MRC stands. Birch heights were similar to spruce neights both before and after crushing. 3•::;>-- .. ' ~~soen. Aspen densitv increased after crushino ir~ all mature stards, siGrifi-·----·---· ., -... cantlj' S;) in ::hr.ee cf tt1em. Response of .:s:·..::n :~-vus~1ir:g ir: r::-r;re,.,. .. ~_·. :':":!',-:: 1vas poor; density in a11 but one stand remained simiiar tc pre-cru:;hi!19 df:nsit:t. .~ ~?·) C;.r;r~ t .. suckeri ng was the probable cause of i ncre,::sed Jens; tyJ Willow. Willow density increased in all Wi1low L~ke stands but decre~s~d in a11 but one MRC stand. -At l~illow Lake, l'tillow occurred ir. sômples ·ir. three stands after crushing where it had not been dete:ted before crushin~. A~ MRC, decreases in two of the stands were statistical !y sign{ficant. Heit;hts of . ~ 1vi1lO\'I and aspen were similar before and after· cl·ushing ir. bot!1 area:, and aver- aged about 52 cm. Bath species are heavily brov;sed each year, and this i:.Jro·ûsing over the 30-year petiod since the fi re may be r.::c f-3ctor causinq lo1.,r density. !\eria1 Caver Survey ~ Wi1lo\v Lake. Significant changes occur:·ed in aeria1 cover of several herbaceous and low-growing woody species. · Fireweed (Epilobium angustifolium) increa~ed in six of ten stands; however, four of those six were . mature stands. Because fireweed is known as ân invading species after distür- bance, this observation was expected. Aeri a 1 co ver of grasses tended to i ncrease a fte_r c rush i ng. Fi ve of se ven stands showed increases, but the change was statistically significant in only one stand. The fern,Gymnocarpium dryopteris, decreased in all four.of the stands tvhere it occurred. Three of those 'I'Jere matur~ stands and the fourth ':135 a :':laper birc~ regrowth stand adjacent ta mature timber. Prick1y ~ose (Rosa acicularis) --~ decreased in seven of nine stands where it occurred. Rose reproduces by seed, ~ so reestablishment would be slmv if killed by the crushing. Starf10i'ler (7rit>nll._-. ~·-· lis ~;paea) ~over increased in all six of the stands in ..,;hien it occurred. It renrod:;ces frofl'l t~hi zomes and perhaps vJas s ti !T!u L=.ted by crush i ng. :; At: ri al cove1· of l ovtbush cranberry { Vac_ç in: 'll!l '{_i_~j_g_-i.fJ..Q~~J decrea~ed i r1 ei~iiH. ,~f ten stands. ï!Jose deçrease5 ·,.;ere s:atis~~(;;11:: si~r:ifi(..;::t. ~-" :;e'lt"::r: of ti1~ stands. Large ci rcul ar a reas of dead l ovtbush cranberry a re commor. ly obsened during the summer and appear to be where moose have .Oug ~Jugh th~ sn01-; to eat the plant .. Plant morta) ity in these areas 15 prob3.b1; _d·.;~? trJ fl·eezing rather than overbrowsing by moos·e. Crushing exposes Jare ground and cor.1pacts snow, reducing its insulation capacity; thus,. the der.:rease ctJser·,etj in 1 owbush cranberry aeri al co ver in our study ::; tands ma:: v1e1l be due to freezing. At HRC) aeri a 1 co ver in uncrushed stands adjoi ni ng r,s tands 5-05, 5-21 , and 5-24 were samp 1 ed. Differences bet\-1een the crus !led and uncrushed ; t'l.O.Qs were -similar to the responses observed at Willow Lake. Fire1·1eed caver v1as greater while prickly rose and lowbush cranberry caver was less in the crushed than un- cr·us!1ed stands. Grass caver was lmver at ~îRC crushed plots in contrast to the higher cover at Wi1low Lake. Lichen response at rvtRC Nas different than \~illow Lake. Peltigera sp. was significantly lo\•Jer in t'.·JO of t~1ree crushed stands and f!_adonia sp. \vas significantly higher in t\-10 of three crushed stands.· At ~:i11ow Ld~:e opposite responses v-1ere observed. Soils. Physical characterists of soi1s in the two areas are not strikingly different (Tables 4 & 5). At MRC, pH and percent clay were significantly higher than at Willow lake. Thicknesses of horizons were not different between the two al~eas. CONCL:JSIONS Crushing has not been totally effective in achieving a11 the desired changes in vegetation compositiqn. Spruce density was successfullv reduced and should not provide a major c3mpetitive factor for 15-29 vears. "-!. -~ Jf- 7 ~- ' ' Aeria1 caver of fireweed, grasses, staJ~f1o\·ter, a'!d Peltigera_ l ich~ns ~n- c reased in mast ·of the stands l'l'he re th ev cc cu rred. Co·li~~-8f -:r-,:: fe;n ( 'j .t:·:r:o-, . ........_ carpi um dryopteri s, rose, and 1 owbush cr a nberry decrea sed after crush i ng. l..o~·t- "' ... ;:!.-.. ,1 -'f!"'..#. bush cr~nberry is an important winter food plant for moose in this area (Le Resche and Davis 1973, Oldemeyer et al. 1977). :·Jhile aeria1 caver cf lo·;~bush cranberry was significantly reduced by crushing, it shou1d recover raoidly because of its--high seed proâuction and mat forming chan~cteristics. One ob- jective of the tree crushe~ program is ta create a multi-species browse range for rnoose. If we succeed in this objective, decreased .caver of lowbu:.il cran- berry will not be important. However, when there is only a single browse species, lov1bush cranberry becomes an important second forage in the winter for moose. -~' ' ., 9 Table ?. Woody plant density before and after crushing at the Moose Research Center. . .. ------------··----uefü 1 a PopultÏs----·---Sallx Picea ___ ,.. ____ a _ _E~ri fe'r:_a_ .. tremu1oides sp muriana S ta ~-------~ef 5> re J\fter Before After Be fore After Bef ore -t,fte-t~--------!· 5-01 5,200 800* 800 400 800 600 8,000 .800* 5-02 43,600 2,400* 600 200 1 ,400 400 6,200 800* ·,' 5-03 25,600 3,200* 800 --1 ,600 400* 7 ,800 BOO* 1 5-04 10,000 3,800* ----1 ,400 1,opo 12,000 5,400* 5-05 9,600 1 ,400* 1 ,400 --5,000 1 ,400* 15,800 2,400* 5-06 600 200 4,600 11 ,800 . 400 --600 400 '·' 5-07 28,200 7,000* --1 ,800 1 ,600 3,200 19,800 1 ,800*w 5-21 4,200 3,400 400 400 800 200 11 ,000 2,000* 1 5-24 400 200 --------12,400 1 ,600 t'> wvlhi te spruce *The probability of the before density being different from the after density ij-}-0.90. ~ü "'' ~ L1ule 2. \~ooJy plant Jensit.y hefore and after crushing at the Hoosc P-esearch Cente1·. -------·-----------~--------------------------------------·--------------------------· --------------·--------------·-----·-• Bct~ _a l Popul~s Sal ix Pi~ea ;\· __ __[J_c~.l!J.!ltet·a_ _trenn!]_!?ld~ ____ _21? _______ . __ _!!lUrlj_l_!_~~'--·--~ ta ~~r! ~-___ ll_~f.~_!"_g ______ Aj ter ___ Bef ore __ __Aj_t_g!' ______ B ~ .f.9E~ ___ }._f t ç-~--_____ .Q_~ for~-----~-!~ r S-Cil ~i-02 ~;-o3 ~i-04 ~)-05 5-06 5-07 5-21 5-24 5,200 43,600 {~5 '600 10,000 9,600 600 28,200 4,200 400 "'l·lh i te s pruce 1 iiOO* 2,400* 3 ,200*. 3,800* 1 ,400* 200 7,000* 3,400 200 ç;, 800 600 800 1 ,400 400 200 4,600 11 ,800 1 ,800 400 400 f\00 1 ,400 1 ,600 1 ,(lOO 5,000 400 1 ,600 800· 600 400 400* 1 ,000 l ,400* 3,200 200 8,000 6.200 1 ,800 12,000 15,800 1 600 19,800 11 ,000 12,400 HOO*· 800* BOO* 5,400* ?.,400* 400 1 ,800*W 2,000* 1 ,600 --------------·------ "The prübability of: the before density being different from the after density is ?-'1.9(). ,, ~ --- 1 0 Table 3. Cove1~ of importè.nt und ers tor; pl :3nts and of debris after crushing at ~lllow Lake and the Moose Research Center. ~ &;;~:~l WillOVI Lake Moose Research Center No. !·lean No . :1ean- . ~ . .Pee i es Stands Caver Stands (O'Ier _ ~.e:tu1a ~rifera. 9 1.0 6 0.5 C1adonia sp. 8 1.2* 9 3 ~* .!) Cornus canadensis 10 3.7* '9 2. 1 * Oebri s 10 5.9 t:g il ~ .. " Epilobium angustifolium lü 2.0 9 ~1.9 Grami nae 6 0.6) 7 0.4 Linnea ba rea 1 i s 8 1. 2* ,. 0.4* 0 . LYS9.P..odi um sp. 7 1.0 9 1.1 Moss es 10 3.8 9 4.2 Pelti_g_t;r~ sp. 7 2.7 8 4.6 Vaccinium vitis-idaea 10 2.7 9 6.7 *Tile probabi 1 i ty th at the mean caver at Hi 11 ow Lake i s different from the Moose Research Cer.ter is .? 0.90. ,,. .. TJble 4. Organic and A Horizon Pararnetr::rs at \·:i11o;·J Lak~ And trJe t·bosE: Research Cente(. ~ .... , A He ri zon Oepth of Rocks Organic Thickness and Stand i1a teri a 1 cm pH Debris Sand si 1t Clat C-01 5 4 4.3 4.4 76.6 22.0 4.4 -C-02 . 9 ·. -7 4.2 0.1 72.6 22.0 5.4 c:o3 .. 7 6 4.5 0.3 71.6 22.0 6.0 C-04 5 5 4.0 0 72.0 22.0 6 (1 . ~ C-05 5 3 4.4 0.2 77.6 17.3 5. 1 C-06 6 2 4.3 0.3 ·58. 9 35.6 5.5 C-07 4 6 3.9 0.9 71.2 24.4 4.4 C-08 8 3 4.3 5.2 "82. 2 15.0 2.8 C-09 10 3 4.2 0. 1 74.7 19.7 5.6 C-10 5 4 4.3 o. 1 76.2 18.6 -s-: 2 Mean 64.4 43 4.2 1.2 73.4 21.9 5.0 5-01 8 4 4.4 0. 1 68.7 25.2 6. 1 5-02 9 2 4.8 0 60.5 30.6 8.9 5-03 6 2 4.5 0.1 55.7 33.9 10.5 , 5-04 12 5 5.4 0.2 64.8 26.7 8.5 5-05 8 2 4.9 0.4 66.3 25.3 8.4 5-06 9 4 4.8 o. 7 77.8 16.9 5.4 5-07 7 6 4.6 0.2 76.3 15.2 8.0 5-21 5 3 4.3 0.9 73.4 21.9 4.7 5-24 5 4 3.8 0.7 78.6 17.2 4.3 Mean 7.7 ~.6 4.6* 0.4 69.2 23.7 7.2* *The probability of the Wiilow lake value being different from the Moose Research Center value is;;. 0.90. ~--"J~ 1 1 ' ) 1 "- Table 5. S and C Horizon Par~tileters at ~1i1ls\·J Lake an~ the Moose Researc~ Cen:e~.~ ~ B Ho ri zan ~ &.:.~ .... , -':JIIJ' -Depth to Thickness C Horizon Stand cm QH Debris Sand s i1 t C1av cm C-Ol 34 5.6 0.2 70. 1 23.9 6.0 tP ,J C-02 64 5.9 0.5 76.3 19.3 4.5 30 C-0.3 76_ ---5.2-o. 1 73.3 21.3 5.4 89 C-04 ____ 3s---5.4 0. 1 74.0 20.2 5.8 45 C-05 '60 5.6 0.6 72.3 22.0 5.2 68 C-06 24 6.3 1 o. 9 79.7 l 5. 7 4.6 30 C-07 56 5.0 0.5 75.2 19.2 5.7 66 C-08 59 5.2 15.2 88.5 7.4 4. l 70 C-09 25 5.5 2.2 77.1 l;.J . !) q_g 38 C-10 21 5.6 3.2 74.6 19. 1 6.2 30 Mean 45.4 5.5 3.4 76.2 13.6 ~ ? J-<-55.9- 5..:01 39 5. 5 0.4 71.1 23.2 5.7 51 5-02 6 5.4 16.0 86.0 9.7 , ~~ '+ . .J 17 5-03 25 5.6 0. l 75-.4 19.4 5.2 33 5-04 13 5.7 1.6 73.6 21.3 5. 1 30 5-05 26 5.7 3.0 82.3 13.0 4.7 ')~ .JO 5-06 76 5.8 0.9 68.7 27.3 4.0 89 5-07 42 5.7 0. 1 81.7 12.6 5.9 55 5-21 65 5.8 2.8 75.4 19.5 5. J 73 5-24 33 5.8 0.7 71.8 23.5 4.7 42 ~1ean 36.1 5.7 2.8 76.2 18.8 5.0 47.3 *The ;Jl~obability of the Willow Lake value being different fr·om the Hoose Research Center corresponding va1ue is f: 0.90. _ .. "J'~ 1 .) ' LITERA TURE C ITEO Daubenmire, R. 1959. A canopy-coverage method of vegetational ana1ysis. ~Northwest Sei. 33{1):43-64. ~,.. .. s Kl·efti ng, L. W. 1974. The eco logy·· of Isle Royale Hoose ~>li tl"i spec i a 1 reference to the habitat. Univ. Minn. Agric. Exp. Sta. Tech. BulL 297. For. Ser. 15. 75 p. LeResche, R. -(. and -J. I. Davis. 1973. Importance of nonbrm·tse foods to moose on the Kenai Peninsula, Alaska. j, ;·Iildl. l1ar,age. 37(3) :279-287. ~- Lutz, H. L. 1956. Ecological effects of forest fires in the interior of Alaska. U.S.D.A. Tech. Bul1. 1133. 121 p. Oldemeyer, J. L. 1975. Characteristics of paper birch saplings browsed by moose and snowshoe hares. Proc. 1lth No. Amer. i·~oose Conf. & Workshop. Winnipeg. Pages 53-62. __ ,A. \1. Franzman, A. L. Brundage, P. O. Arneson, and A.1 Flynn, 1977. Brm·;se quality and the Kenai moose population. J. :·!ildl. l~anage.' 41 (3) :533-542. Peek. J. 1·1., O. L. Urich, R. J. Macki-e. 1976. Moose habitat se1ection and relationships to forest management in northeastern Minnesota. Wildl. Monog. 48. 65 p. Spencer, O. l. and J. B. Hakala. 1964. Moose and fire on the Kenai. Ta11 Timbers fire Ecol. Conf. 3:10-33. 1elfer. f.. S. 1972. The effect of logging on wildlife_ in the boreal forest. Paper ;n-esented-to Ann. ~1eet. Can. Soc. Wildl. & Fish Biol., Saskatoon. Q ( • 1 .-p . , rn 1 meo .. '