Soil Amendments and Planting Techniques: Campsite Restoration in the Eagle Cap Wilderness, Oregon

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1 Soil Amendments nd Plnting Techniques: Cmpsite Restortion in the Egle Cp Wilderness, Oregon Dvid N. Cole Dvid R. Spildie Astrct Results of the first three yers of revegettion reserch on closed wilderness cmpsites re descried. Experimentl tretments involved soil scrifiction, n orgnic soil mendment ( mix of loclly collected orgnic mterils nd pet moss nd n inocultion of ntive undistured soil), n orgnic mtter nd composted sewge sludge tretment nd surfce ppliction of commercil mulch (Bionet). Hlf of the experimentl plots received ntive seed nd trnsplnts; the other hlf did not. Seeding nd trnsplnting were highly successful. The orgnic nd compost soil mendment gretly incresed seedling growth nd incresed trnsplnt growth somewht. Scrifiction incresed seedling estlishment of volunteer seedlings. On federl lnds designted y Congress s Wilderness, mngement ojectives stress protection of nturl conditions. Despite this emphsis on protection nd preservtion, wilderness res re typiclly open to recretion use, nd resultnt impcts cn e severe, prticulrly on cmpsites. Most cmpsite impct is ccepted s necessry if recretion use is to e llowed. However, in some situtions, cmpsite impcts re deemed to e either excessive or inpproprite in tht prticulr loction. In these situtions, wilderness mngers close sites to cmping so they cn return to conditions pproximting those tht existed prior to disturnce. Where recovery rtes re slow, mngers often employ vrious restortion tretments in n ttempt to ccelerte successionl processes (for exmple Lester 1989). These efforts re often costly, in terms of time nd money, nd frequently re not very successful (for exmple Moritsch nd Muir 1993). In mny wilderness ecosystems, little is known out fctors tht limit the rte of nturl recovery or out the effectiveness of techniques designed to ccelerte recovery. Consequently, we designed study to ssess the effectiveness of severl common restortion tretments on closed cmpsites in high sulpine forests in the Egle Cp Wilderness, in northestern Oregon. Specific ojectives were to ssess the influence of (1) mending soils with orgnic mtter, composted sewge sludge nd ntive soil inoculum, (2) trnsplnting nd seeding with locl, ntive species, In: Cole, Dvid N.; McCool, Stephen F.; Borrie, Willim T.; O Loughlin, Jennifer, comps Wilderness science in time of chnge conference Volume 5: Wilderness ecosystems, threts, nd mngement; 1999 My 23 27; Missoul, MT. Proceedings RMRS-P-15-VOL-5. Ogden, UT: U.S. Deprtment of Agriculture, Forest Service, Rocky Mountin Reserch Sttion. Dvid N. Cole nd Dvid R. Spildie re Reserch Biologist nd Biologist t the Aldo Leopold Wilderness Reserch Institute, Rocky Mountin Reserch Sttion, Forest Service, U.S. Deprtment of Agriculture, P.O. Box 8089, Missoul, MT U.S.A. nd (3) pplying surfce mulch on the estlishment, survivl nd growth of vegettion. Study Sites The study is eing conducted in the Lkes Bsin portion of the Egle Cp Wilderness, Wllow-Whitmn Ntionl Forest, northestern Oregon. This re, locted etween 2,170 m nd 2,320 m, contins numer of sulpine lkes. Locted km from the closest trilheds, the Lkes Bsin ttrcts lrge numers of wilderness cmpers. Cmpsite impcts round these lkes re sustntil nd numerous (Cole 1981, 1993). Erly efforts to close nd restore cmpsites egn in the 1970s. These efforts were lrgely unsuccessful. Cmpsites tht hve een closed to use hve experienced little recovery over period of more thn decde (Cole nd Hll 1992). Six cmpsites were selected for restortion in All re in sulpine forest consisting of Aies lsiocrp, Pice engelmnnii, Pinus contort nd Pinus liculis. The most common groundcover plnts, in undistured plces, re Vccinium scoprium, Phyllodoce empetriformis nd Crex rossii. Soils re derived from grnitic sustrte. All re within 70 m of lkes nd, therefore, hve een illegl cmpsites for more thn 15 yers. However, ll of these sites received some cmping use over this period, hd virtully no groundcover vegettion nd hd not een revegetted in the pst. These sites hve proly exhiited high levels of impct (soil compction, lck of vegettion nd miniml soil orgnic horizons) for t lest 50 yers. Prior to restortion efforts, these cmpsites were typiclly out 200 m 2 in size, with out 100 m 2 completely devoid of vegettion. Methods Ech cmpsite ws divided into two whole plots, one with nd one without surfce mulch ppliction. Ech whole plot ws sudivided into six plots, which received comintions of the two fctors: soil mendments (orgnics/inoculum; orgnics/inoculum/compost; or nothing) nd plnting (trnsplnted/seeded; or nothing). All 12 of these 1.5 m y 1.5 m plots were scrified. An dditionl plot, the control, received no tretment t ll. The six cmpsites provide six replictes. Tretments Scrifiction utilized shovels, picks, pitchforks, hoes nd hnd kneding to rek up compction nd clods to depth USDA Forest Service Proceedings RMRS-P-15-VOL

2 of out 15 cm. We tried to void turning over the soil, ut sustntil mixing of soil horizons ws unvoidle in our resolve to develop crum texture. On severl sites, numerous tree roots were cut nd removed during scrifiction. This intensity of scrifiction exceeds tht commonly undertken. Tretments tht received the orgnics/inoculum tretment were covered with mix of pet moss nd welldecomposed, loclly collected orgnic mtter to depth of out 2.5 cm. The dry pet moss ws mixed with wter efore ppliction. This mteril ws then mixed with minerl soil to depth of 7.5 cm. Inoculum cme from the rooting zone of locl trnsplnts tht were eing trnsplnted onto the site. Aout 1.2 liters of soil were mixed with out 20 liters of wter to mke slurry. Three liters of this slurry were sprinkled over ech plot nd rked into the soil. Compost tretments hd orgnic mtter nd inoculum dded in n identicl mnner. In ddition, we dded 2.5 cm of composted sewge sludge (Ekocompost from Missoul, Montn), lightly wtered nd rked into the top 10 cm of orgnic nd minerl soil. Hlf of the plots were seeded nd trnsplnted. Seeding involved (1) collecting seed loclly from severl species with mture seed, (2) division of ville seed into equl quntities for ech seeded plot, (3) pinch-rodcsting seed over the plot, nd (4) rking seed into the upper 2.5 cm of soil. Seeded species vried etween cmpsites nd included Antennri lnt, Aster lpigenus, Dnthoni intermedi, Juncus prryi, Penstemon prryi, Phleum lpinum, Sitnion hystrix nd Sildi procumens. Loclly ville seed ws unusully limited due to the unusully short growing seson in One of the cmpsites (t Crescent Lke) ws not seeded due to lck of mture seed in the vicinity. Trnsplnting involved (1) digging up enough trnsplnts in the vicinity to plnt equl numers of ech species in ech plot, (2) digging hole nd plcing trnsplnts in the hole, long with Vit-strt (vitmin B-1) to reduce trnsplnt shock, nd (3) giving ech trnsplnt 0.6 liters of wter. Plots tht were not plnted were given n equivlent mount of wter. Most trnsplnt plugs were etween 5 nd 25 cm in dimeter, nd most plots received five to six plugs. Although most plugs contined only one species, some contined more thn one. Trnsplnted species vried etween cmpsites nd included Aies lsiocrp, Achille millefolium, Antennri lpin, Antennri lnt, Aster lpigenus, Clmgrostis cndensis, Crex rossii, Dnthoni intermedi, Gultheri humifus, Hypericum formosum, Juncus prryi, Luzul hitchcockii, Oryzopsis exigu, Phyllodoce empetriformis, Pinus contort, Polemonium pulcherrimum, Sildi procumens, Spire etulifoli nd Vccinium scoprium. All seeding nd trnsplnting occurred in the centrl 1 m 2 of ech plot. Mesurements were lso confined to this centrl re, leving 1 m uffer etween the mesured portion of ech treted plot. Hlf of the plots were covered with iodegrdle erosion control lnket mde of strw interwoven with cotton string nd jute (Bionet). The lnket ws held in plce with rocks. Where there were trnsplnts, string ws cut to llow the trnsplnts to penetrte the strnds of strw. Ech cmpsite ws closed to use y locking min ccess points with string nd n ovious sign. No evidence of cmping use hs een oserved since cmpsites were closed to use. In 1996, when it ppered tht soils were extremely dry, plots were wtered severl times. When this ws done, ll plots were given n equl mount of wter. No supplementl wtering ws done in lter yers. In ll four yers of the study, the lte snowpck ws unusully deep, suggesting tht erly seson conditions were much less droughty thn norml. In 1996, the first growing seson fter restortion, when plots were occsionlly irrigted, the summer ws dry ut cool. In 1997, the summer ws cool nd wet. In 1998, the summer ws hot nd dry, nd plnts were not given supplementl wter. In 1998, t Aneroid Lke, locted t similr elevtion in n djcent dringe, the men mximum tempertures in July were 5-7 degrees Celsius higher thn in 1996 or At Mt. Howrd, the closest site with precipittion dt, July-August precipittion ws 18 cm in 1997, compred with 7 cm or less in 1996 nd Mesurements For ech trnsplnt, we mesured rel extent of cnopy cover (using 1-m squre PVC frme with 5-cm y 5-cm grid) nd mximum height. Mesurements were tken immeditely fter trnsplnting (Septemer 1995) nd in Septemer of 1996, 1997 nd Seedling estlishment ws ssessed eginning in erly July Every two weeks from erly July to erly Septemer (four times), ll estlished seedlings were mpped. Ech seedling ws identified y species, nd colored toothpick ws plced next to it to denote dte of estlishment. This mde it possile to ssess period of estlishment nd deth, if mortlity occurred. In 1997, seedlings tht germinted in 1996 were identified on the sis of their size, loction nd species. New seedlings (the 1997 cohort) were identified in the surveys conducted every two weeks. In some plots, seedlings were so numerous tht they were ssessed in suplots. In 1998, seedling ssessment occurred twice, in mid-july nd erly Septemer. Agin, we ttempted to differentite etween new seedlings (the 1998 cohort) nd older plnts. Ten individuls of seeded species were rndomly selected on ech plot, nd their height ws mesured in Septemer of 1996, 1997, nd In 1996 nd 1997, nother four individuls of the sme species were crefully excvted. Their root nd shoot iomss ws mesured, following clening nd drying. In 1998, we mesured the height of the tllest individul of the seeded species, which we hd found to e well-correlted with iomss. This voided the need for further destructive smpling. In 1997 nd 1998, height nd iomss mesurements were tken only on seedlings tht germinted nd estlished in Trnsplnt rel extent nd seedling loctions were digitized to llow sptil nlysis. Tretment effects were nlyzed using stndrd sttisticl techniques, primrily t-tests nd nlyses of vrince, with post-hoc Duncn s multiple comprisons. Results In Septemer 1995, totl of 206 plugs were trnsplnted onto 36 of the 78 plots. These plugs contined 280 individul 182 USDA Forest Service Proceedings RMRS-P-15-VOL

3 trnsplnts (either seprte species, seprte individuls or seprte verticl stems tht might e seprte individuls). By Septemer 1996, 96% of these plugs nd 92% of the individul trnsplnts were still t lest prtilly live. By Septemer 1997, 96% of the originl plugs were still living, nd the numer of live individul trnsplnts (382) exceeded the numer pprent t the time of plnting. Trnsplnt mortlity ws greter during the hot, dry summer of Nevertheless, y Septemer 1998, 90% of the originl plugs nd 86% of the originl trnsplnts were still living (tle 1). In 1998, the numer of live individul trnsplnts (318) still exceeded the numer of individuls pprent t the time of plnting. The men cnopy cover of surviving trnsplnts (rel extent) decresed 5 cm 2 (5%) etween Septemer 1995 nd Septemer By Septemer 1997, men cnopy cover ws 113 cm 2 ; y Septemer 1998, men cnopy cover ws 151 cm 2. In three yers since trnsplnting, then, the men cover of surviving trnsplnts incresed 52 cm 2 (55%). The totl cover provided y ll trnsplnts ws 33% greter in 1998 thn in 1995, when trnsplnting occurred. Men trnsplnt height declined 4% (from 7.6 cm to 7.3 cm) during the first yer following trnsplnting. By Septemer 1997, men trnsplnt height ws 10.2 cm. By Septemer 1998, men trnsplnt height ws 12.6 cm. After three yers, men trnsplnt height ws 66% greter thn t the time of trnsplnting. In 1997, 12% of the trnsplnts flowered. Forty percent of trnsplnts flowered in During the summer of 1996, lmost 20,000 seedlings germinted nd estlished on the 78 1 m 2 plots. Most of these seedlings (>70%) germinted from the seed we hd rodcst. However, volunteers germinted from seed tht reched the site through nturl dispersl processes or, perhps, from the soil seednk. In 1996, most of the volunteers were perennil species; in 1997 nd 1998, most volunteers were nnul species. Germintion nd estlishment continued throughout the two-month ssessment period (erly July to erly Septemer). However, out two-thirds of the seedlings estlished (cotyledons were well-developed) in the erly August period out one month fter snow hd left most plots. Germinnts were proly emerging from the soil out two weeks prior to the point t which we considered them estlished. In 1997, the 1996 seedling cohort generlly emerged erly, y mid- to lte July. The 1997 seedling cohort estlished throughout the seson, ut primrily in erly August. The 1997 cohort of seeded species ws out one-third s undnt s the 1996 cohort (fig. 1). The 1997 cohort of volunteer perennils ws out one-hlf s undnt s the 1996 cohort. However, nnuls were out four times more undnt in 1997 thn in In 1997, the totl numer of seedlings tht either re-emerged (the 1996 cohort) or ecme estlished (the 1997 cohort) on the 78 1 m 2 plots exceeded 25,000. The 1998 cohort of seeded species ws smll, only out 2% s undnt s the originl 1996 cohort. The 1998 cohort of volunteer species ws similr in quntity to the 1997 cohort, out one-hlf of the 1996 cohort. Annul species Summer 1996 Fll 1996 Summer 1997 Fll Summer Fll 1998 Seeded Perennils Cohort Cohort Cohort Volunteer Perennils Cohort Cohort Cohort Volunteer Annuls 1996 Cohort 1997 Cohort 1998 Cohort Figure 1 Seedling density (#/m 2 in squres) nd survivl rtes (in tringles) of seeded species nd volunteers from cohorts of seedlings tht estlished in 1996, 1997, nd Tle 1 Men (stndrd error) plug nd trnsplnt survivl, growth nd flowering, Chnge in Chnge in Trnsplnt Tretment Plug survivl Trnsplnt survivl trnsplnt re trnsplnt height flowering Percent (cm 2 ) c (cm) c Percent Soil mendment None 88(4) 84(4) 30(12) 4.4(0.8) 42(4) Orgnics 89(4) 87(4) 49(25) 5.7(0.7) 76(32) Orgnic/compost 92(4) 89(4) 76(12) 7.6(1.2) 35(4) Mulch tretment None 90(3) 85(3) 36(15) 6.0(0.7) 60(22) Mulched 89(3) 89(3) 67(19) 5.8(0.8) 42(4) Totl 90(2) 86(2) 52(12) 6.0(0.5) 51(11) Mens with different letters re significntly different ( = 0.05). Plugs nd trnsplnts (individul species within plug) plnted in 1995 still live in c Chnge etween time of plnting in 1995 nd USDA Forest Service Proceedings RMRS-P-15-VOL

4 were extremely undnt. In 1998, the totl numer of seedlings tht either re-emerged or ecme estlished on the 78 1 m 2 plots ws out 16,000, 36% less thn in Seedling density vried gretly etween the six cmpsites. Seedling survivl vried etween yers nd sesons, s well s etween seeded species nd volunteers (fig. 1). We could not ssess mortlity prior to seedling estlishment (the emergence of well-developed cotyledons). However, once estlished, there ws virtully no mortlity (< 1%) of seeded species during the summer of 1996, when plots were occsionlly wtered, nd the summer of 1997, which ws wet. For volunteer perennil species, mortlity rtes were slightly higher, 12% in the summer of 1996 nd out 5% in For oth seeded nd volunteer species, mortlity during the winter of ws out 35-40%. Overll, out 65% of the seedlings tht estlished in 1996 were still live in fll of Mortlity within the 1996 cohort ws more thn offset y germintion nd estlishment of dditionl seedlings in Aout 17,000 perennil seedlings were live on the 78 1 m 2 plots in Septemer 1996; out 18,000 perennil seedlings were live in Septemer Winter mortlity rtes were lower during the winter of % for seeded species nd 15% for volunteer perennils. However, mortlity rtes during the hot, dry summer of 1998 were high, prticulrly for seeded species nd for the smll 1998 cohort. Close to one-hlf of the seedlings tht re-emerged or estlished in 1998 hd died y Septemer Aout 10,000 perennil seedlings were live on the 78 1 m 2 plots in Septemer The proportion of perennil seedlings tht were volunteers incresed from 16% in 1996 to 35% in The sptil pttern of the initil cohort of seedlings ws nlyzed with GIS. The 1996 cohort of seedlings ws neither regulrly nor rndomly distriuted. They were ggregted to significnt degree. Seeded species were more ggregted thn volunteers. This suggests tht ggregtion resulted from oth the seeding process nd the vilility of sfe sites. Seedling density ws greter outside trnsplnt plugs thn within, ut seedlings were ttrcted to the trnsplnts (tht is, they were locted closer to trnsplnts thn expected). Seeded nd volunteer species did not differ in the extent to which they were less undnt under trnsplnts or more undnt close to trnsplnts. This suggests tht conditions close to trnsplnts fvor seedling estlishment, while conditions underneth trnsplnts discourges estlishment. It is uncler whether these sptil ptterns result from trnsplnt effects on seed dispersl-entrpment ptterns, soil conditions, microclimtic conditions or competitive interctions. Tretment Effects Survivl of trnsplnts ws high (out 86%) regrdless of tretment (tle 1). Between 1995 nd 1998, increse in cnopy cover (rel extent) of trnsplnts ws significntly greter on plots with the orgnic nd compost soil mendments thn on scrified plots tht received no soil mendments (fig. 2). Increse in height ws lso significntly greter on orgnic nd compost plots (tle 1). Compred to plots without surfce ppliction of mulch, mulched plots experienced greter increse in cnopy cover ut smller increse in height. Neither of these differences ws Chnge in Trnsplnt Are (cm 2 ) None Orgnics Orgnics & compost Soil Amendment Mulch Tretment Figure 2 Effect of soil mendments nd mulch on increse in cnopy cover of trnsplnts, 1995 to Verticl rs indicte one stndrd error; different letters indicte significntly different mens (α = 0.05). sttisticlly significnt, however. Trnsplnt flowering ws highest on plots tht received orgnic soil mendments ut no compost, s well s on plots without mulch tretment. This response ws highly vrile within tretments, however, nd differences re not sttisticlly significnt. The effect of scrifiction on seedling density ws ssessed y compring the nonscrified control plot with plots tht were scrified ut received no other tretment. On these two sets of plots, ll estlished seedlings re volunteers. In 1998, scrified plots hd significntly greter seedling density (men of 31 seedlings/m 2 ) thn control plots (7 seedlings/m 2 ) (fig. 3). Seeding hd tremendous influence on seedling density, with seeded plots hving over five times s mny seedlings s unseeded plots, three yers fter seeding. Volunteers were eqully undnt on seeded nd nonseeded plots. Plots tht were mended with orgnic mtter nd compost hd significntly more seedlings thn unmended plots. However, the surfce mulch tretment did not hve significnt effect on totl seedling density, the density of seeded species or the density of volunteers. Explntions for differences in seedling density vried etween the tretments. Scrifiction ws dvntgeous to seedling estlishment. The scrified plots included in the nlysis were not seeded, nd their mortlity rte ws not significntly lower thn tht on controls. Seeding ws dvntgeous ecuse it provided more undnt source of propgules. Despite higher mortlity rtes on seeded plots (tle 2), seedling density remins higher on seeded plots. The orgnic/compost mendment ws dvntgeous ecuse mortlity rtes during the hot, dry summer of 1998 were lower thn on other plots (tle 2). Propgule vilility nd estlishment rtes were no greter on orgnic/ compost plots. After the moist 1996 nd 1997 summers, seedling density ws not greter on the orgnic/compost plots. More thn one-third (36%) of the seedlings tht re-emerged or estlished during the hot, dry summer of 1998 died, No Yes 184 USDA Forest Service Proceedings RMRS-P-15-VOL

5 Seedling Density (#/m 2 ) No Yes No Yes No Yes None Orgnics Orgnics & compost Scrifiction Soil Amendments Mulch Seeding Figure 3 Effect of scrifiction, soil mendments, mulch nd seeding on seedling density, Septemer The scrifiction tretment reported received no soil mendment, mulch or seeding. Verticl rs indicte one stndrd error; different letters indicte significntly different mens (α = 0.05). Men Seedling Height (cm) None Orgnics Orgnics & compost Soil Amendment c No Yes Mulch Tretment Figure 4 Effect of soil mendments nd mulch on increse in men height of 3-yer-old seedlings, Septemer Verticl rs indicte one stndrd error; different letters indicte significntly different mens (α = 0.05). Tle 2 Seedling density in Septemer 1998 nd seedling mortlity nd flowering during Seedling Seedling Seedling density mortlity flowering (#/m 2 ) Percent Soil mendment None 103(31) 33(7) 7(4) Orgnics 134(42) 23(4) 5(2) Orgnics/compost 187(67) 13(3) 15(4) Mulch tretment None 152(39) 24(4) 9(3) Mulched 131(28) 21(4) 9(3) Seeding tretment None 51(19) 17(3) 9(3) Seeded 267(55) 32(6) 9(2) Scrifiction tretment None 7(4) 36(18) 0(0) Scrified 31(17) 23(4) 20(16) Totl 141(28) 23(3) 9(2) Mens with different letters re significntly different ( = 0.05). Scrified tretment received no soil mendment, mulch or seed. lthough the men seedling mortlity rte for the plots ws just 23%. Nine percent of surviving seedlings flowered in Flowering rtes were significntly higher on the plots tht were mended with orgnic mtter nd compost thn on unmended plots or plots mended with just orgnic mtter nd soil inoculum (tle 2). Seedling growth ws influenced y oth soil mendments nd mulching (fig. 4). In Septemer 1996, the men height of seedlings of selected seeded species ws 1.7 cm. Seedling height ws significntly greter on plots tht received either the orgnics mendment (men of 1.8 cm) or the orgnics nd compost mendment (1.9 cm) thn on plots without mendments (1.5 cm). Seedling height ws lso significntly greter on mulched plots (2.0 cm) thn on plots without mulch (1.5 cm). By Septemer 1997, the men height of seedlings estlished in 1996 hd incresed to 3.5 cm, nd it ws possile to confidently guess plot s soil tretment simply y oserving seedling roustness. Men height incresed to 5.7 cm in In 1997 nd 1998, seedling height on the plots with the orgnics nd compost mendment ws significntly greter thn on plots receiving orgnics or no soil mendments t ll. Plots mended with orgnics hd tller seedlings thn unmended plots (fig.4). Seedling height ws lso significntly greter on the mulched plots thn those without mulch, in oth 1997 nd For the selected seeded species, the men iomss of seedlings tht estlished in 1996 incresed from 12 mg in 1996 to 190 mg in Their root:shoot rtio incresed from 0.34 in 1996 to 0.52 in In oth 1996 nd 1997, seedlings on plots mended with orgnics nd compost hd significntly more iomss thn seedlings on other plots. Root:shoot rtios did not differ significntly with soil tretment, lthough they were higher on the orgnics (0.65) nd orgnics nd compost plots (0.55) thn on plots without soil mendments (0.37). Greter iomss of individul seedlings might prtilly explin the lower seedling mortlity rtes on the plots with orgnic nd compost mendments. Mulching hd no effect on iomss in either yer. Vegettion cover ws negligile efore restortion. Immeditely fter trnsplnting nd seeding, men totl cover ws 3.7%. Men cover incresed to 9.0% in 1996, 10.6% in 1997 nd 13.2% in 1998 (tle 3). Most cover ws initilly provided y the trnsplnts. By 1997 nd 1998, however, more cover ws provided y plnts tht germinted from seed. Although initilly most of the plnts tht germinted from seed were seeded species, the proportion of volunteers hs incresed every yer. Plnting ws the tretment tht hd the most drmtic effect on cover. Men cover exceeded USDA Forest Service Proceedings RMRS-P-15-VOL

6 Tle 3 Cnopy cover of trnsplnted, seeded, nd totl vegettion, Septemer Cnopy cover Trnsplnted Seeded Totl Percent Soil mendment None 5.0(1.2) 5.1(2.5) 9.2(2.8) Orgnics 6.0(1.7) 6.8(1.5) 12.4(2.6) Orgnics/compost 7.4(2.0) 11.8(2.6) 18.1(3.6) Mulch tretment None 5.7(1.2) 6.9(1.7) 11.8(2.3) Mulched 6.6(1.5) 8.9(2.1) 14.6(2.7) Plnting tretment None 0(0) 4.8(1.1) 4.5(1.1) Plnted 12.3(1.3) 11.0(2.3) 21.9(2.7) Scrifiction tretment None 0(0) <0.1(0) <0.1(0) Scrified 0(0) 1.2(0.6) 0.8(0.5) Totl 6.2(0) 7.9(1.3) 13.2(1.7) Mens with different letters re significntly different ( = 0.05). 20% on plnted plots ut ws less thn 5% on plots tht were not plnted. The plots mended with orgnic mtter nd compost hd twice the men cover of plots tht were not mended. Plots tht were mulched nd scrified lso hd more cover thn plots tht were not treted, ut differences were not sttisticlly significnt. Discussion nd Conclusions Overll, the restortion techniques we employed were highly effective. Virtully ll of the trnsplnts survived the procedure. Most were growing vigorously nd mny were flowering three yers fter plnting. Soil mendments (orgnic mtter, soil inoculum nd composted sewge sludge) contriuted gretly to the vigor of trnsplnt growth. The surfce mulch hd no cler effect, either positive or negtive. Although seedling density vried gretly etween cmpsites, the men seedling density of perennil species on seeded plots ws 267 seedlings/m 2 three yers fter seeding. Seedlings were growing vigorously. Men seedling iomss incresed more thn ten fold during the second growing seson, nd men seedling height incresed 68% during the third growing seson. Scrifiction, seeding nd the orgnic nd compost soil mendment were ll effective in incresing seedling density. Scrifiction nd seeding hd more effect on seedling estlishment, while the soil mendment hd more effect on seedling survivl during the hot, dry summer of The orgnics nd compost tretment ws most effective in enhncing seedling growth. This effect of soil mendments only ecme pprent in the second growing seson. The surfce mulch nd orgnics tretments hd less pronounced positive effects on seedling growth, which only ecme pprent in the third growing seson. The high level of seedling estlishment nd survivl on ll seeded plots during the first two growing sesons nd the reltive ineffectiveness of the mulch tretment were two surprising results. Both results might e explined y the unusul climtic conditions tht persisted over the first three summers of fieldwork. In ll three yers, lte snow comined with frequent summer rinfll ment tht soil moisture levels were proly reltively high. With undnt soil moisture, seedling germintion, estlishment nd survivl might hve een unusully high, even without some of the microclimtic meliortion tht surfce mulch cn provide. The third growing seson ws hot nd dry, nd seedling survivl declined drmticlly. Seedling mortlity ws much lower where soils were mended with orgnic mtter nd compost, perhps result of incresed soil wter-holding cpcity nd seedlings with etter developed root systems. This suggests tht supplementl wtering my e criticl to effective restortion during yers with hot, dry summer wether. Supplementl wtering my e needed for severl yers, prticulrly where soils hve not een mended with orgnic mtter. It is quite possile tht much of our success with seeding ws the result of the supplementl wtering done when seedlings were germinting during the initil growing seson following seeding. The unusully high intensity of scrifiction we employed my lso prtilly ccount for our success. Projected recovery rtes vry gretly etween tretments. Men vegettion cover on undistured stnds close to cmpsites is out 55% (Cole 1982). Plots with the orgnic nd compost mendment tht were scrified, plnted nd mulched hd men cover of 35% in This mounts to more thn 60% recovery in just three yers. Projecting pst recovery rtes into the future, plots receiving this most eneficil tretment would experience complete recovery of cover in out five yers. On plnted plots without soil mendments, recovery would require out 10 yers. On plots tht re scrified ut neither mended nor plnted, recovery would require more thn 100 yers. Without scrifiction, recovery would tke even longer. Although more thn 60% recovery of plnt cover in three yers seems successful, composition hs not recovered s rpidly s cover. On restored sites, grminoids constitute more thn 50% of the vegettion cover compred to out 25% on undistured sites (Cole 1982). On undistured sites, the two low shrus, Vccinium scoprium nd Phyllodoce empetriformis, ccount for 28% nd 11% of the vegettion cover, respectively. On restored sites, they ccount for 7% nd 4% of the cover, respectively. Compositionl recovery will require mny decdes unless trnsplnting, prticulrly of shrus, is done t densities tht mimic undistured conditions. We recommend tht closed sites remin signed nd roped off t lest until vegettion cover on restored sites pproximtes pre-disturnce conditions. Even with effective restortion techniques, it will likely require hundreds of yers to eliminte the undesirle nd unnecessry cmpsite impcts in the Lkes Bsin nd confine impcts to the levels nd plces deemed cceptle. This suggests the importnce of voiding dmge in the first plce, y implementing effective mngement progrms wherever regulr recretion use occurs. 186 USDA Forest Service Proceedings RMRS-P-15-VOL

7 Acknowledgments We pprecite the field ssistnce of Jeff Comstock nd mny personnel from the Wllow-Whitmn Ntionl Forest, prticulrly Tom Crlson. The use of trde nmes in this pper is for reder informtion nd does not imply endorsement y the U.S. Deprtment of Agriculture of ny product. References Cole, D. N Vegettionl chnges ssocited with recretionl use nd fire suppression in the Egle Cp Wilderness, Oregon: some mngement implictions. Biologicl Conservtion. 20: Cole, D. N Wilderness cmpsite impcts: effect of mount of use. Resrch Pper INT-284. Ogden, UT: U. S. Deprtment of Agriculture, Forest Service, Intermountin Reserch Sttion. 34 p. Cole, D. N Cmpsites in three western wildernesses: prolifertion nd chnges in condition over 12 to 16 yers. Reserch Pper. INT-463. Ogden, UT: U. S. Deprtment of Agriculture, Forest Service, Intermountin Reserch Sttion. 15 p. Cole, D. N. nd T. Hll Trends in cmpsite condition: Egle Cp Wilderness, Bo Mrshll Wilderness, nd Grnd Cnyon Ntionl Prk. Reserch Pper INT-453. Ogden, UT: U. S. Deprtment of Agriculture, Forest Service, Intermountin Reserch Sttion. 40 p. Lester, W. J Revegettion efforts t North Cscdes Ntionl Prk Service Complex. In: Hughes, H. G.; Bonnicksen, T. M. (eds.). Restortion 89: the new mngement chllenge. Proc. First Annul Meeting of the Society for Ecologicl Restortion; 1989 Jnury 16-20; Oklnd, CA. Mdison WI: Society for Ecologicl Restortion: Moritsch, B. J. nd P. S. Muir Sulpine revegettion in Yosemite Ntionl Prk, Cliforni: chnges in vegettion fter three yers. Nturl Ares Journl. 13: USDA Forest Service Proceedings RMRS-P-15-VOL