Assessment of Whitebark Pine Regeneration in Burned Areas of the Shoshone and Bridger-Teton National Forests and Wind River Reservation, Wyoming

Transcription

1 Assessment of Whitebrk Pine Regenertion in Burned Ares of the Shoshone nd Bridger-Teton Ntionl Forests nd Wind River Reservtion, Wyoming Finl Report For Agreement No. 07-CA Region 1 nd 4 USDA Forest Service Forest Helth Protection 3815 Schreiber Wy Coeur d Alene, ID Februry 1, 2008 Authors: Jennifer G. Klutsch 1,2, Betsy A. Goodrich 1, nd Willim R. Jcobi 1 Coopertors: Elizbeth Dvy 3, Ellen Jungck 4, Eric Rhodenbugh 5 Funding: USDA Forest Service, Region 1-4, Whitebrk Restortion Funds 1 Dept. of Biogriculturl Sciences nd Pest Mngement, Colordo Stte University, Ft. Collins, CO ; 3 USDA Forest Service, Bridger-Teton Ntionl Forest, Jckson, WY 83001; 4 USDA Forest Service, Shoshone Ntionl Forest, Dubois, WY 82513; 5 US DOI Bureu of Indin Affirs, Deprtment of Forestry, Wind River Reservtion, Fort Wshkie, WY Corresponding uthor phone: (970) , fx: (970) , e-mil: Jennifer.Klutsch@colostte.edu). 1

2 Summry Whitebrk pine (Pinus lbiculis Englem.) forests in northwestern Wyoming, including the Wind River Reservtion, Shoshone Ntionl Forest nd Bridger-Teton Ntionl Forest, hve been severely ffected by mountin pine beetle (Dendroctonus ponderose Hopkins) (MPB)-, wildfire-, nd white pine blister rust (Cronrtium ribicol J.C. Fisch.) (WPBR)- induced mortlity. In previously burned res, there is limited criticl informtion on the regenertion of whitebrk pine seedlings. The purpose of this study ws to determine nd compre the mount of regenertion in burned nd non-burned res, nd to determine wht site fctors impcted regenertion occurrence. A survey of whitebrk pine regenertion in six res tht hve experienced stnd replcing fires 8 to 32 yers previous ws conducted in the Wind River nd Absrok Mountin Rnges in summer Fires were divided into polygons of similr spects, elevtions, nd forest types. Potentil seed source ws mesured in surrounding forests. Tree regenertion ws tllied by species, nd height clss; nd stndrd tree mesurements, including MPB nd WPBR incidence, were tken for whitebrk pine long with site nd stnd conditions in burned nd non-burned res. The mount of regenertion ws vrible for ll species nd more thn 25% of the plots did not hve whitebrk pine. Aspect of the site ws relted to the density of whitebrk pine regenertion in burned res. The mount of whitebrk pine regenertion smller thn 200cm tll in burned res on south fcing slopes ws 7.6 stems/h (hlf LSD = +15.8, -5.1) nd stems/h (hlf LSD= , ) on north fcing slopes (p=0.0508). Site nd stnd conditions, such s vegettion type, mount of potentil seed source, nd mount of other species regenertion were positively relted to the density of whitebrk pine regenertion in burned res. The lrgest percent of whitebrk pine regenertion occurred under the protection of downed woody debris, logs nd roots in both the burned nd 2

3 non-burned res (63.9% nd 47.3%, respectively). The percent of live whitebrk pine infected with WPBR ws generlly low for most fires nd rnged from 0 to 10.7%. The loss of mture, cone bering trees to the current MPB outbrek will impct the future potentil for whitebrk pine regenertion for most of the fires surveyed. Burned res with cool nd wet north fcing slopes with potentil seed source within the rnge of the Clrk s Nutcrcker (Nucifrg columbin Wilson) my be res where whitebrk pine will regenerte, while south fcing slopes or res with mostly grss cover my either tke longer thn north fcing slopes to regenerte or my not regenerte to whitebrk pine without the help of rtificil plnting. Introduction Whitebrk pine (Pinus lbiculis Englem.) is ssumed to be fire-dependnt for regenertion. In the southern extent of the species, the Wind River Mountin region, there is limited criticl informtion on the survivl of whitebrk pine seedlings in previously burned res. Whitebrk pine is vitl to high elevtion lpine ecosystems. Birds, specificlly the Clrk s Nutcrcker (Nucifrg columbin Wilson), nd severl mmml species rely on the lrge seeds for sustennce. In effect, the only form of seed dispersl for whitebrk pine is by wy of the Clrk s Nutcrcker; nd cching sites re usully in open res, such s those creted by recent fires (Tombck 2001). Whitebrk pine on the Wind River Reservtion, s well s the Shoshone nd Bridger- Teton Ntionl Forests hs been severely ffected by mountin pine beetle (Dendroctonus ponderose Hopkins) (MPB)-, wildfire-, nd white pine blister rust (Cronrtium ribicol J.C. Fisch.) (WPBR)-induced mortlity. Likewise, restortion ctivities in the region would benefit from informtion on the survivl nd helth of whitebrk pine regenertion in previously burned 3

4 res. The objective of this study ws to: 1) determine the incidence of whitebrk pine regenertion in previously burned res compred to unburned res; 2) determine wht site nd stnd fctors re relted to the presence of whitebrk pine regenertion; nd 3) document the incidence nd severity of dmge gents on whitebrk pine regenertion nd mture trees, such s white pine blister rust nd mountin pine beetle, in burned nd non-burned res. Mterils nd methods Plot Loctions nd Smpling Permnent regenertion monitoring plots were estblished in non-burned forested res nd forested res burned 8 to 32 yers previous, with totl of 6 fires smpled (Fig. 1, Tble 1). Smpled fires were in res of potentil whitebrk pine hbitt defined by elevtion nd surrounding vegettion nd within n hour hike from rod in the Shoshone NF, Bridger- Teton NF, nd Wind River Reservtion (Fig. 1). Fires were divided into polygons of similr spects, elevtions, nd forest types; with ech polygon comprising minimum re of burned forest of 1.76h (80m x 220m) nd n ssocited minimum re of non-burned forest of 1.10h (50m x 220m). A totl of 14 polygons were surveyed. Trees, long with ny regenertion, within polygon were smpled within plots plced long trnsect tht followed elevtionl contours. In burned res, three to five trnsects were rndomly selected from the mximum number of trnsects tht would fit inside the polygon. The two trnsects plced in non-burned res were selected in the sme mnner s burned res. The ends of trnsects were 10m from the nerest non-burned re in burned portions of polygon nd 10m from the nerest burned re in non-burned portions of polygon. 4

5 Trnsects in both burned nd non-burned res were monumented with tgged nd red or yellow pinted rebr nd tgged nd pinted log, tree or stump. A trnsect consisted of minimum of 5 plots, ech 2m by 40m in length. Every other plot ws skipped in lrge polygons to mximize the distnce long trnsect within polygon smpled. A minimum of 30m nd mximum of 100m existed between two djcent trnsects within polygon. A totl of 396 plots were mesured, with 256 plots in burned res nd 140 in non-burned res. Within ech plot on the trnsect, the number of ech tree species present within height clsses (< 20cm, cm, cm, cm, 300cm) were tllied, nd for whitebrk pine, crown clss, microsite conditions, helth clss, biotic or biotic dmge incidence nd dmge severity were collected. Microsites were clssified s: bse of tree or under low tree cnopy; under protection of downed woody debris, logs, or roots; open, no protection from wind or solr; under protection of rocks; nd in crcks or holes in trees. Helth clss ws on scle from 1 (helthy) to 5 (ded without fine twigs or needles). The spect (degrees, ctegorized s north nd south), percent slope, disturbnce types (crown fire, surfce fire, slvge logging, selective cuts, burn piles, plnting or interplnting of seedlings), percentge of top three species of ground cover, percentge of bre ground, percentge of litter, nd percentge of surfce re disturbed by pocket gophers (Thomomys tlpoides) were recorded. Vegettion ws ctegorized s either ssocited with wet or dry site conditions. Vccinium scoprium ws the mjor species ssocited with cool nd wet conditions (Arno, 2001). The species ssocited with dry site conditions were: Crex spp., Juncus spp., Arnic cordifoli, nd bunch grsses (Arno, 2001). The bsl re of ll tree species long with helth clss, dmge gent incidence, dmge severity, whether cones hve been present nd dimeter clss were ssessed t the ends of ech 5

6 plot using bsl re ngle guge (5 BAF (ft 2 /cre) in burned res nd 10 BAF (ft 2 /cre) in non-burned res), long with recording GPS coordintes. In severl of the permnent reserch plots, there were indictions of tree interplnting. To determine which trees were plnted, the ge of five-needle pine regenertion ws determined by counting brnch whorls, with trees of the sme ge s plnted regenertion excluded from most nlysis. Determintion of the species of five-needle pine regenertion ws not possible so species designtion ws bsed on surveying surrounding mture, live white pine species. Regenertion ws ssumed to be whitebrk pine if the surrounding forest consisted only of whitebrk pine nd not limber pine. The differentition of mture whitebrk pine from limber pine ws by comprison of mle nd femle cones. Seed Source To ssess the nerest whitebrk pine seed source, non-burned forest 10m from the perimeter of the fire ws surveyed with vrible rdius plots, ech recording the bsl re of ll tree species long with the helth clss, dmge gent, dmge incidence nd severity, dimeter clss nd whether whitebrk pine or limber pine cones were present. Vrible rdius plots were spced 80m prt nd surrounded the fire in potentil whitebrk pine hbitt. Meterologicl dt Monthly verges of precipittion, nd minimum nd mximum tempertures t four Ntionl Ocenic nd Atmospheric Administrtion wether sttions surrounding the Wind River Mountin Rnge were obtined from the Ntionl Climtic Dt Center. Wether sttions used were: Lnder, Jckson, Morn, nd Dubois, WY. 6

7 Dt nlysis Tests for sptil uto- nd cross-correltion between plots within fires (p<0.05) were performed using sptil proximity weights equl to the inverse of the distnce between plots, defining neighborhood for ech fire tht rnged from 10 to 45m. Anlysis of sptil correltion ws crried out using R (The R Foundtion for Sttisticl Computing, 2007) with dditionl functions to clculte nd test Morn s I (Robin Reich, Colordo Stte University, personl communiction). To determine differences in tree density between burned nd non-burned res, nd north nd south fcing slopes, mixed model nlysis of vrince ws run with spect nd sttus s fixed effects nd polygon, trnsect, plot s rndom effects (SAS/STAT 9.1, MIXED procedure). Since sptil correltion ws observed, the coordintes ssocited with ech plot were used to fit sptil power model for the residuls. The density of trees ws positively skewed nd to meet the ssumption of normlity, the dt ws trnsformed to the log 10 scle for nlysis. The bcktrnsformed dt is presented which corresponds more to the medin thn to the men (Jmes zumbrunnen, Colordo Stte University, Sttisticl Lbortory, personl communiction). Results Stnds in this study consisted of mix of whitebrk pine, Engelmnn spruce (Pice engelmnnii Prry ex Engelm.), sublpine fir (Abies lsiocrp [Hook.] Nutt.) nd lodgepole pine (Pinus contort Dougls ex Louden), with the proportion of ech species differing for ech fire (Tble 1). Though limber pine ws encountered t two of the fires, Unit 40 nd Willow Creek, smpling did not occur t lower elevtion portions of the fire where limber pine occurred 7

8 nd regenertion ws considered whitebrk pine bsed on the whitebrk found in the surrounding higher elevtion res. Tree Regenertion The density of whitebrk pine ws vrible, with more thn 25% of the plots without the presence of whitebrk pine (Tble 2). The bck-trnsformed djusted mens for the density of whitebrk pine within height clsses ws noticebly lower thn the men not trnsformed nd not ccounting for the experimentl design (Tble 2). The mount of whitebrk pine regenertion, seprted into height clsses, were significntly lower in burned res thn in non-burned res nd rnged from 1.3 to 12.3 stems/h in burned res nd 3.2 to 65.2 stems/h in non-burned res (Fig. 2). Whitebrk pine density ws not significntly different on different spects when ll plots were within the model. Covrites tht were positive in these models were the percent cover of vegettion ssocited with wet conditions, density of ll other species (seedlings to mture trees), nd density of only lodgepole pine (seedlings to mture trees). Percent cover of litter ws negtive covrite in the model for the density of whitebrk pine tht ws cm in height. Grouping the three shortest height clsses together (whitebrk pine less thn 200cm in height), there ws significnt interction between spect nd whether the plot ws in burned or non-burned re (Tble 3). South fcing slopes tht hd burned hd significntly less number of whitebrk pine smller thn 200cm in height thn on north fcing spects nd non-burned res (Tble 3). The percent cover of vegettion ssocited with wet conditions ws positive covrite for this model. When removing non-burned plots from the models, the density of whitebrk pine seprted into height clsses were greter on north spects compred to south spects for the two 8

9 lowest height clsses (whitebrk pine less thn 100cm in height) (Fig. 3). Covrites tht were positive in the models for the height clsses < 100cm in height were: bsl re of nerest whitebrk pine potentil seed source, percent cover of shrubs, number of yers since the fire, nd density of lodgepole pine (seedlings to mture trees). Percent cover of grss nd minimum distnce to potentil whitebrk pine seed source were negtive covrites. Whitebrk pine were found growing in clusters of 2 to 10 trees, with n verge of 3.1 ± 0.12 whitebrk pine per cluster. There ws n verge (bck-trnsformed from log 10 ) of 7.7 clusters/h (hlf LSD= +1.7, -1.3). In ddition to whitebrk pine, the regenertion species were: sublpine fir, Engelmnn spruce, lodgepole pine, nd to miniml degree, Dougls-fir (Pseudotsug menziesii [Mirb.] Frnco) on the Willow Creek Fire. As with the whitebrk pine regenertion, there ws significnt vrition in the density of regenertion (Fig. 4). Compring density of regenertion in burned nd non-burned res, only Engelmnn spruce hd lower densities of regenertion in burned res thn non-burned res though this does not reflect the ge structure of the regenertion (Fig. 4). The mount of regenertion for non-whitebrk pine species ws not significntly different on north slopes compred to south slopes. Site nd Stnd Conditions Relted to Regenertion The potentil whitebrk pine seed source ws considered mture trees tht were cone bering or hd the potentil to be cone bering. The verge minimum distnce for ech fire from plots to potentil seed source rnged from 89.7 to m. The bsl re of mture live whitebrk pine tht were potentilly cone bering rnged from 3.2 to 7.0 m 2 /h for ech fire. Bre ground nd litter rnged from 0 to 80% cover nd from 0 to 60% cover, respectively. Vegettion ssocited with wet conditions (Vccinium scoprium) ws 9

10 component in 25% of the plots nd rnged from 1 to 60% cover. Ninety-three percent of the plots hd component of vegettion ssocited with dry conditions nd rnged from 2 to 100% cover. After ech fire, there were fluctutions of dry/hot nd wet/cool periods (Fig. 5). Most mesures of regenertion nd stnd chrcteristics hd positive sptil uto- nd cross-correltion t the plot level for ll of the fires except for Willow Creek. The percent cover of grss nd vegettion ssocited with dry site conditions generlly hd negtive sptil crosscorreltions with most regenertion nd stnd mesures. In 4 of the 6 fires, there were either negtive or null sptil cross-correltions of the density of other species or lodgepole pine regenertion to the density of whitebrk pine regenertion. The microsites with downed woody debris, logs nd roots were where lrge percentge of whitebrk pine tht were less thn or equl to 100cm in height were found (Tble 4). In the burned re, there were significntly less whitebrk pine regenertion under the protection of tree bses or under low tree cnopy compred to non-burned res, which is likely relted to the lck of cnopy cover in burned res (Tble 4). The ge of whitebrk pine ws estimted by counting the number of whorls for trees less thn or equl to 100cm in height. Whitebrk pine less thn 20cm in height nd 20 to 100cm in height were younger in the burned res compred to the non-burned res (p-vlue=0.0522, p= respectively) (Tble 5). A regression nlysis on the ge of whitebrk pine to height in the burned nd non-burned res shows tht the slopes of the trend lines re different, though the trjectories re similr (Fig.6). The presence of hrvesting, domestic grzing, nd pocket gophers ws not significntly relted to the mount of whitebrk pine regenertion found in burned or non-burned res. Hrvesting nd grzing occurred in the burned nd non-burned res in 68% nd 46% of the 10

11 plots, respectively. In the burned res, slvge logging occurred 85% nd grzing in 51% of the plots. Pocket gophers nd their tunnels were present in 54% of the burned plots nd 16% of the non-burned plots. The Geyser Creek, Unit 40, Willow Creek, nd Dry Cottonwood fires were plnted, t lest 6 yers prior to the survey, with lodgepole pine, though the success of these plntings were different for ech fire nd within ech fire. The plnting of lodgepole pine t the Willow Creek fire ws generlly not successful becuse of period of drought when the trees were plnted (Eric Rhodenbugh, Deprtment of Forestry, Wind River Reservtion, personl communiction). At the Geyser Creek, Unit 40 nd Dry Cottonwood fires, rtificil regenertion ws successful on north fcing slopes. The interplnting of whitebrk pine t the Geyser Creek fire ws generlly unsuccessful on the south fcing slope due to exposure to the wind nd solr rdition, long with hevy snow drifts during the winter (Ellen Jungck, Shoshone Ntionl Forest, personl communiction). Dmge Agents Ded tops nd browsing or rubbing from nimls were mjor dmges on whitebrk pine regenertion in both burned nd non-burned res (Tble 6). Incidence of WPBR occurred in ll height clsses except for trees less thn 20cm in height (Tble 6). The mount of infection in burned nd non-burned re ws less thn 6.4% of totl whitebrk pine density (seedlings to mture trees) (Tble 6). Both WPBR nd MPB ctivity occurred in the non-burned forest. The incidence of live whitebrk pine (with mesurble DBH) infected with WPBR rnged from 0 to 10.7%, with low verge severity for infected trees (0 to 14% stems infected) except for whitebrk pine in the Unit 40 re (50% stems infected) (Tble 1). Mountin pine beetle hd been cusing mortlity in 11

12 the whitebrk pine before nd fter the fires. The time since mortlity by mountin pine beetle ws estimted by the mount of brk nd brnch degrdtion nd whether ded trees were burned in the fire. The estimtes of MPB-induced mortlity tht occurred before the fires rnged from 0 to 22% of the density of susceptible (DBH>20.3cm) whitebrk pine (Tble 1). Also, there ws extensive recent mortlity tht hd occurred since the fires due to MPB tht rnged from 17.1 to 51.5% of the density of susceptible whitebrk pine (Tble 1). Discussion The density of whitebrk pine regenertion in burned nd non-burned res ws vrible, nd does seem to be relted to specific site nd stnd chrcteristics. Ech fire hd different conditions tht contributed to the mount of whitebrk pine regenertion, such s spect, vegettion type, non-burned tree species composition, nd the mount of potentil seed source. The cool nd wet site conditions on northern slopes long with the success of other species of regenertion were positively relted to the density of whitebrk pine regenertion in burned res. The conditions tht mke other tree species successful lso mke whitebrk pine regenertion successful, though these conditions my be spotty throughout the burned res. Becuse spect ws significnt fctor in the mount of regenertion in burned res, there is evidence tht dry nd hot periods my negtively ffect successful whitebrk pine regenertion. More reserch should be conducted on the survivl of seedlings during yerly shifts in temperture nd precipittion. The high yerly temperture nd low yerly precipittion fter the most recent fire - Moccsin Bsin Fire in long with the southerly fcing slope, my hve hd n effect on the potentil for regenertion nd my be prtilly responsible for the lck of regenertion of ny tree species t this site. 12

13 The plnting of lodgepole pine in 4 of the 6 fires my hve ffected the density of whitebrk pine regenertion by either deterring cching of seeds by birds or by competition. However, beyond the sptil nlysis tht showed there ws trend towrds negtive to null cross-correltion of whitebrk pine regenertion to the mount of lodgepole pine regenertion there ws little evidence tht the mount of lodgepole pine regenertion (which tended to be mostly rtificilly plnted) ws preventing the successful regenertion of whitebrk pine. Regenertion density for whitebrk pine nd Engelmnn spruce were greter in nonburned res s compred to burned res. Though the density of whitebrk pine regenertion ws less in burned res, the regenertion grew more rpidly nd hs much greter potentil of becoming mture cnopy trees thn do the over-topped regenertion in non-burned res. The microsite conditions where seeds were cched were ssocited with objects, such s logs nd bses of trees, my lter the moisture nd temperture of site nd be more fvorble for regenertion growth. A greter percentge of whitebrk pine regenertion ws found in microsites creted by downed woody debris, logs, nd roots. Similrly, Tombck et l. (1993) found the gretest occurrence of whitebrk pine regenertion in burned res ner smll wood pieces, fllen trees nd brnches. Even in non-burned res in the current study, downed woody debris, logs nd roots were microsites where high percentge of whitebrk pine regenertion occurred, with mjor percentge of whitebrk pine regenertion lso occurring in sites under the protection of low cnopy or bse of tree. Future estblishment of whitebrk pine regenertion my be limited due to the current MPB outbrek in the Wind River Mountin Rnge. This will hinder the successful estblishment of nturl regenertion of whitebrk pine in more recent fires, such s the Bridger-Teton nd Shoshone Ntionl Forest Purdy fire in The MPB-induced mortlity reduces potentil 13

14 seed source nd my lso deter the presence of the Clrk s Nutcrcker while it looks for food in other ecosystems (Tombck & Kendll 2001). Also, the genetic resource for potentil resistnce to WPBR will be gretly reduced due to the extensive mortlity of mture, cone bering trees from MPB infesttion. It is not known if WPBR will sty t the present low incidence in mture nd regenerting whitebrk pine, or increse in incidence s it hs done in stnds to the southest, lso on the Wind River Rnge (Kerns & Jcobi, 2007). Recommendtions for future restortion of serl whitebrk pine in previously burned res include, plnting on north fcing slopes where there re more wet, cool, nd sheltered conditions nd in res with vegettion tht includes Vccinium scoprium. Estblishing whitebrk pine regenertion under the protection of downed woody debris, logs or roots would mimic the nturl plcement of whitebrk pine regenertion by Clrk s Nutcrckers. Also, deterring competition by estblishing seedlings in res without grsses or thick turf corresponds to where whitebrk pine regenertion occurs. These recommendtions should be tested in stnds recently opened up with extensive mortlity due to MPB. The success of nturl nd rtificil interplnting of whitebrk pine in res previously plnted with other species should be reserched. 14

15 References Arno, S.F Community types nd nturl disturbnce processes. In: Tombck, D.F., Arno, S.F., nd Kene, R.E. (eds.), Whitebrk Pine Communities: Ecology nd Restortion. Islnd Press, Wshington, D.C., pp Kerns, H.S.J., nd Jcobi, W.R The distribution nd incidence of white pine blister rust in centrl nd southestern Wyoming nd northern Colordo. Cndin Journl of Forest Reserch 37: Tombck, D.F Clrk s nutcrcker: gent of regenertion. In: Tombck, D.F., Arno, S.F., nd Kene, R.E. (eds.), Whitebrk Pine Communities: Ecology nd Restortion. Islnd Press, Wshington, D.C., pp Tombck, D.F., nd Kendll, K.C Biodiversity losses: the downwrd spirl. In: Tombck, D.F., Arno, S.F., nd Kene, R.E. (eds.), Whitebrk Pine Communities: Ecology nd Restortion. Islnd Press, Wshington, D.C., pp Tombck, D.F., Sund, S.K., nd Hoffmn, L.A Post-fire regenertion of Pinus lbiculis: height-ge reltionships, ge structure, nd microsite chrcteristics. Cndin Journl of Forest Reserch 23:

16 Tble 1. Burned res smpled in 2007 in the northern Wind River nd southern Absrok Mountin Rnges, WY. Bridger- Teton NF/ Jckson Shoshone NF/ Wshkie District District Wind River Reservtion Fire nme Geyser Unit 40 Moccsin Dry Willow Crow Creek Bsin Cottonwood Creek Creek Fire yer Are burned (h) NA NA Averge elevtion (m) Number of polygons North fcing South fcing Number of plots in burned re Number of plots in non-burned re Species composition trees with DBH/h Whitebrk Pine Englemnn Spruce Sublpine Fir Lodgepole Pine % stems/h of live WB 3.5% 10.7% 0% 3.9% 4.2% 2.6% infected with WPBR Averge WPBR severity of infected WB 2 Post-fire MPB 22.5% 51.5% 42.5% 37.1% 17.1% 1.4% Pre-fire MPB 18.8% 2.6% 0 9.7% 22.3% 0.2% 1 Polygons re defined s being mde up of burned nd non-burned re tht hve similr spects, elevtions, nd forest type. 2 White Pine Blister Rust (WPBR) severity: 0 to 9 with rting of 0=0-9% ffected, 1=10-19% ffected 9=90-100% ffected. Note: Whitebrk pine is bbrevited s WB, mountin pine beetle s MPB, nd dimeter t brest height s DBH. 16

17 Tble 2. Descriptive sttistics for the density of live whitebrk pine in height clsses in burned nd non-burned res in the northern Wind River nd southern Absrok Mountin Rnges, WY. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not included. Live whitebrk pine (stems/h) < 20cm cm cm cm >300cm men SE mximum rd qurtile medin st qurtile minimum Tble 3. Adjusted men density of live whitebrk pine (bck-trnsformed from log 10 ) in burned nd non-burned res, nd north nd south spects in the northern Wind River nd southern Absrok Mountin Rnges, WY. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not included. whitebrk pine regenertion less thn 200cm in height (+/- hlf LSD) north spect (n=157) (274.5, 104.0) burned south spect (n=99) 7.6 b (15.8, 5.1) north spect (n=90) (428.0, 148.7) non-burned south spect (n=50) (351.1, 102.4) Note: Different letters denote significnce t p < Mens djusted for percent vegettion cover ssocited with wet site conditions. 17

18 Tble 4. Percent of live whitebrk pine 100cm in height nd bck-trnsformed (from log 10 ) men density by microsite clssifiction in the northern Wind River nd southern Absrok Mountin Rnges, WY. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not included. Burned re Non-burned re (n=256) (n=140) Bse of trees or under low tree cnopy % stems in burned re stems/h (+/- hlf LSD) (1.2, 0.7) % stems in nonburned re stems/h (+/- hlf LSD) (14.4, 8.1) p-vlue Under protection of downed woody debris, logs, or roots (12.5, 6.0 ) (23.8, 11.0) Open, no protection from wind or solr (2.1, 1.1) (2.9, 1.4) Under protection of rocks (0.4, 0.3) (0.5, 0.3) In crcks or holes in trees (0.1, 0.1) Tble 5. Men number of whorls on live whitebrk pine (bck-trnsformed from log 10 ) in burned res nd non-burned res in the northern Wind River nd southern Absrok Mountin Rnges, WY. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not removed from nlysis. Height of live whitebrk pine Burned re (+/- hlf LSD) Non-burned re (+/- hlf LSD) p-vlue < 20cm 3.7 (0.8, 0.7) 5.6 (0.8, 0.7) cm 11.4 (1.3, 1.1) 18.0 (1.7, 1.5)

19 Tble 6. Density nd percent ffected of whitebrk pine with dmges (bck-trnsformed from log 10 ) in burned nd non-burned res on whitebrk pine in the northern Wind River nd southern Absrok Mountin Rnges, WY. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not removed from nlysis. Burned (n=256) Non-burned (n=140) Men stems/h +/- hlf LSD % of live WB Men stems/h +/- hlf LSD % of live WB p-vlue Ded top , , Animl dmge , , WPBR , , < 20* * , , * , , * , , >300* , * Stems/h of dmged whitebrk pine is divided by the density of live whitebrk pine within the corresponding height clss to obtin percent ffected. 19

20 Figure 1. Burned res smpled in 2007 in the northern Wind River nd southern Absrok Mountin Rnges, WY. Unit 40 Moccsin Bsin Dry Cottonwood Creek Geyser Creek Crow Creek Willow Creek Are of Interest Legend Fires smpled Shoshone NF Bridger-Teton NF Wind River Reservtion 20

21 live whitebrk pine (stems/h) Figure 2. Adjusted men density of live whitebrk pine (bck-trnsformed from log 10 ), by height clss in burned nd non-burned res in the northern Wind River nd southern Absrok Mountin Rnges, WY b burned re (n=256) non-burned re (n=140) b b b b < >300 height clss (cm) Note: Error brs re hlf LSD. Different letters denote significnce t p<0.05 within height clsses. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not included. Density of live whitebrk pine in height clss <20cm is djusted for percent cover of vegettion ssocited with wet site conditions. Density of live whitebrk pine in height clss cm is djusted for trees/h of lodgepole pine (seedlings to mture trees). Density of live whitebrk pine in height clss cm is djusted for trees/h of ll species (seedlings to mture trees) other thn whitebrk pine nd percent cover of litter. Density of live whitebrk pine in height clss >300cm is djusted for percent cover of vegettion tht is ssocited with wet site conditions. 21

22 live whitebrk pine (stems/h) Figure 3. Adjusted men density of live whitebrk pine (bck-trnsformed from log 10 ) in burned res in the northern Wind River nd southern Absrok Mountin Rnges, WY north spect (n=157) south spect (n=99) 40 * 20 0 b ** < >300 height clss (cm) Note: Error brs re hlf LSD. * denotes significnt difference from ** t p<0.10 within height clss. Different letters denote significnce t p<0.05 within height clsses. Trees potentilly plnted in the Geyser Creek nd Unit 40 fires were not included. Density of live whitebrk pine in height clss <20cm is djusted for trees/h of ll species (seedlings to mture trees) other thn whitebrk pine, bsl re of nerest whitebrk pine potentil seed source, nd percent cover of shrubs. Density of live whitebrk pine in height clss cm is djusted for time since fire, percent cover of grss, minimum distnce to potentil seed source, nd trees/h of lodgepole pine (seedlings to mture trees). Density of live whitebrk pine in height clss cm is djusted for time since fire. Density of live whitebrk pine in height clss cm is djusted for time since fire, trees/h of lodgepole pine (seedlings to mture trees), nd percent cover of vegettion tht is ssocited with dry site conditions. Density of live whitebrk pine in height clss >300cm is djusted for time since fire. 22

23 live lodgepole pine (stems/h live sublpine fir (stems/h live Englemnn spruce (stems/h Figure 4. Density of sublpine fir, Engelmnn spruce, nd lodgepole pine (bck-trnsformed from log 10 ) by height clss in burned nd non-burned res in the northern Wind River nd southern Absrok Mountin Rnges, WY. A. sublpine fir; B. Englemnn spruce; C. lodgepole pine. Error brs re hlf LSD. A) 140 B) burned re (n=256) 120 non-burned re (n=140) b < > b b b < >300 height clss (cm) height clss (cm) C) < >300 height clss (cm) 23

24 Precipittion (mm) Temperture (Celsius) Figure 5. Averge yerly, winter, nd summer temperture (Celsius) nd precipittion (mm) for 4 NOAA wether sttions in the Wind River Mountin Rnge from 1975 to yerly verge dtes of fires smpled winter yerly verge summer winter verge verge summer verge verge yer yerly verge winter verge summer verge verge yer Note: Averges of temperture nd precipittion were clculted from Ntionl Ocenic nd Atmospheric Administrtion wether sttions surrounding the Wind River Rnge nd obtined from the Ntionl Climtic Dt Center: Lnder (elevtion 1694m), Jckson (elevtion 1899m), Morn (elevtion 2072m), nd Dubois (elevtion 2120m). 24

25 Log10 number of whorls Figure 6. Regression models for height nd log 10 trnsformed number of whorls in burned nd non-burned res in the northern Wind River nd southern Absrok Mountin Rnges, WY y = x R 2 = y = x R 2 = burned non-burned Liner (burned) Liner (non-burned) height (cm) Note: Burned re model: log 10 (# of whorls)=0.0044(height) ; R 2 = Non-burned re model: log 10 (# of whorls)=0.0051(height) ; R 2 =