United States

Department

of Agriculture

Forest Service

Rocky Mountain

Research Station

General Technical

Report RMRS-GTR-185

February 2007

Vegetation and 

Soil Restoration on 

Highly Impacted 

Campsites in 

the Eagle Cap 

Wilderness, Oregon

David N. Cole

David R. Spildie
Cole, David N.; Spildie, David R. 2007. Vegetation and soil restoration on highly impacted campsites in the 

Eagle Cap Wilderness, Oregon. Gen. Tech. Rep. RMRS-GTR-185. Fort Collins, CO: U.S. Department of 

Agriculture, Forest Service, Rocky Mountain Research Station. 26 p.

Abstract

We assessed the effectiveness of planting techniques (seeding and transplanting) and restoration treatments 

designed to improve the physical, biological, and chemical properties of soils and ameliorate microclimatic conditions on six closed campsites in subalpine forests. Restoration treatments included scarification, soil amendment 

with organic matter, compost and soil inoculum, and application of a mulch blanket. Campsite closure, scarification, planting, and soil amendments were successful in increasing recovery rates. The mulch blanket had no 

effect on recovery. 10 years after campsite closure, vegetation cover was still diminished in comparison to reference conditions on nearby undisturbed sites. Particularly problematic was reestablishment of the low-growing 

shrub species (particularly Vaccinium scoparium and Phyllodoce empetriformis) that are the most abundant 

groundcover species in these forests. These species seldom establish from seed. Moreover, survivorship and 

growth rates are unusually low for transplants. Our results show the relative ease of establishing various species and growth forms in these forests, as well as which species and growth forms respond best to the applied 

treatments. Results reinforce the importance of avoiding impacts in the first place, the lengthy recovery periods 

required in these ecosystems, and the intensive restoration efforts needed to speed recovery.

Key words: compost, mulch, recreation impact, scarification, seeding, soil amendments, transplanting

Authors

David N. Cole is Research Biologist with the Aldo Leopold Wilderness Research Institute, Missoula, MT. He received an A.B. degree in geography from the University of California, Berkeley, and a Ph.D. in geography from 

the University of Oregon.

David R. Spildie is a Natural Resources Specialist with Recreation Solutions, Missoula, MT. He was biologist 

with the Aldo Leopold Wilderness Research Institute when this study was conducted.

Acknowledgments

Many individuals contributed to this project. Numerous Forest Service district personnel assisted with implementation of the treatments and study, most notably Tom Carlson, Kendall Clark, and Jerry Hustafa. Many others 

assisted with data collection, most notably Jeff Comstock. Tom DeLuca coordinated analysis of soil samples. 

Neal Christensen and Rudy King assisted with data analysis and Dave Parsons and Jeff Marion provided useful review comments.

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cover photos: (top) Closed campsite at Horseshoe Lake 10 years after restoration 

treatments were applied. (middle) Groundcover vegetation on a 

sample plot, 10 years after scarification, planting and soil amendments. 

(bottom) Amending the soil of a long-disturbed campsite with organic 

matter, compost and native soil inoculum.
Vegetation and Soil Restoration on Highly 

Impacted Campsites in the Eagle Cap 

Wilderness, Oregon

David N. Cole, David R. Spildie

Contents

Introduction.............................................................................................................. 1

Study Sites............................................................................................................... 1

Methods.................................................................................................................... 1

Treatments........................................................................................................ 1

Measurements .................................................................................................. 4

Data Analysis and Presentation........................................................................ 5

Results...................................................................................................................... 5

Effects on Soils ................................................................................................. 5

Effects on Total Plant Cover.............................................................................. 7

Effects on Transplant Cover.............................................................................. 9

Effects on Seedling Cover ...............................................................................11

Seedling Establishment and Mortality............................................................. 15

Effects on Species Richness .......................................................................... 17

Progress in Relation to Reference Conditions................................................ 17

Discussion ............................................................................................................. 19

Treatment Effects............................................................................................ 20

Further Research............................................................................................ 23

Treatment Needs of Individual Species .......................................................... 23

Management Implications..................................................................................... 24

A Prescription for Campsite Restoration......................................................... 24

Restoration and Visitor Management.............................................................. 25

References ............................................................................................................. 26

USDA Forest Service RMRS-GTR-185. 2007 1

Introduction

Subalpine lakes are magnets for recreation use 

throughout the mountainous wilderness of the western 

United States. People flock to these lakes for their outstanding scenic qualities, as well as to fish, swim, picnic, 

and camp. Although use is much greater today than it 

was before the 1960s, some popular lakes have been regularly visited for the better part of a century. Regularly 

visited places, particularly those that serve as campsites, 

quickly become impacted. Understory vegetation disappears, as do organic soil horizons. Exposed mineral soil 

becomes highly compacted, reducing rainfall infiltration 

and increasing erosion.

Wilderness managers are concerned about such 

campsite impacts given their mandate to preserve natural conditions in wilderness. While it is clear that some 

level of impact is inevitable if overnight camping is allowed, these impacts may be more numerous than they 

should be or may be occurring in locations where they 

are considered unacceptable. Increasingly, managers are 

closing impacted sites to camping to allow them to return to pre-disturbance conditions. This goal has often 

proved elusive, however. Recovery cannot occur unless 

all site use is curtailed. Wilderness managers are often 

reluctant to erect the signs and ropes that can be effective in keeping walkers, anglers, and picnickers, as well 

as campers, off closed campsites.

Even where recreational use is effectively curtailed, 

recovery can be an extremely slow process in subalpine 

ecosystems. Growing seasons are short and climatic 

conditions during these seasons can be harsh. Many of 

the abundant subalpine plants establish infrequently and 

grow slowly. Moreover, the soil on many closed sites 

no longer provides a good growing medium for plants. 

Many decades without vegetation and with minimal 

organic input have left the plants physically, biologically, and chemically impoverished. Managers often 

responded by employing various restoration techniques 

in attempts to accelerate successional processes (Lester 

1990). However, these efforts are often costly in terms 

of time and money, and frequently are not very successful (Moritsch and Muir 1993).

Given the lack of information on effective means of 

restoring subalpine campsites, we initiated long-term experiments using several common restoration treatments. 

Specifically, we assessed the effectiveness of (1) scarification, (2) transplanting and seeding with local, native 

species, (3) ameliorating microclimatic conditions with 

a mulch mat, and (4) amending soils with organic matter, compost, and soil inoculum. Treatment effects were 

closely followed for 10 years.

Study Sites

The study was conducted on six campsites in the 

Eagle Cap Wilderness, Wallowa Mountains, northeastern Oregon. All sites were located at an elevation of 2215 

to 2300 m, adjacent to subalpine lakes, about 12 to 15 

km from the closest road. They were located in forests 

with an overstory of Abies lasiocarpa (subalpine fir), 

Pinus contorta (lodgepole pine), and Pinus albicaulis 

(whitebark pine). Ground cover vegetation on adjacent, 

little disturbed sites is discontinuous (typically about 

50 percent cover). Ericaceous dwarf shrubs, Vaccinium 

scoparium (grouse whortleberry) and Phyllodoce empetriformis (red mountain heather), and the caespitose 

graminoids, Juncus parryi (Parry’s rush) and Carex rossii (Ross’ sedge), are the most abundant species.

This plant community type occurs throughout much 

of the western United States at high elevations, particularly in locations that are popular destinations for 

wilderness recreation. The impacts of wilderness camping are probably more common in this community type 

than any other in the United States, making information about effective restoration techniques particularly 

useful in this type. Soils are shallow, sandy, and acidic 

(pH between 4.2 and 4.8) and are derived from granitic substrates (Cryochrepts and Cryorthents). Although 

snow typically covers the ground until late June/early 

July, snowmelt is typically followed by hot, dry summers. The frequency of summer thunderstorms varies 

from year to year. When they are infrequent, soils can be 

highly droughty for several months (most of the growing season).

These campsites have probably exhibited high levels of impact (lack of vegetation, minimal soil organic 

horizons, and compacted mineral soil) for at least 50 

years. Prior to restoration, these campsites were typically about 200 m2

 in size, with about 100 m2 completely 

devoid of vegetation. Soil organic horizons had eroded 

away over substantial portions of these sites and mineral soils were so compacted that infiltration rates were 

reduced by almost 50 percent (Cole and Fichtler 1983). 

Potentially mineralizable N and microbial activity were 

also substantially reduced on these campsites (Zabinski 

and others 2002).

Methods

Treatments

Campsite restoration began in 1995 with the closure of these sites to camping, using closure signs and 
2 USDA Forest Service RMRS-GTR-185. 2007

rope. The closures were highly effective. Over the 10 

years of the study, we found only a few instances where 

it appeared someone had walked on the plots. Nobody 

camped on any of the sites.

A three-factor experiment, using a split plot design 

was employed. Twelve treatment plots (1.5 m by 1.5 

m) were established on each campsite. The soil was 

scarified on these plots. Scarification involved the use 

of shovels, picks, pitchforks, hoes, and hand kneading to break up compaction and clods to a depth of 

about 15 cm. Substantial mixing of soil horizons was 

unavoidable in our resolve to develop a crumb texture. On several sites, numerous tree roots were cut and 

removed during scarification. This intensity of scarification exceeds that commonly undertaken on wilderness 

campsites.

A control plot (not treated in any way) was established within the closed area on a part of the campsite 

that was not scarified. This plot was used in an analysis, 

separate from the factorial experiment, of the effect of 

scarification in the absence of mulch, soil amendments, 

and planting.

Of the three factors in the split plot experiment, the 

mulch treatment was the factor used to establish whole 

plot units because it was most feasible to apply mulch 

blankets over large areas. Six contiguous plots on each site 

were covered with a biodegradable mulch made of straw 

interwoven with cotton string and jute (Bionet®)(fig. 1). 

The other six contiguous plots were not mulched. Within 

each of the two mulch whole plots, three levels of soil 

amendment and two levels of planting were assigned to 

split-plot units in a completely randomized design. Each 

combination of soil amendment and planting occurred in 

each whole plot. Figure 2 illustrates the layout for one of 

the campsites. Each campsite had a unique ordering of 

treatments within the mulch whole plots. Each campsite 

provided one of six replicates.

There were three levels of the soil amendment factor. 

Within each whole plot, two treatment plots (split-plot 

units) received no amendments. Another two plots 

were amended with organic matter and inoculated with 

native soil. The organic matter was a mix of peat moss 

(20 percent) and well decomposed, locally collected organic matter. The dry peat moss was mixed with water 

before application. A 2.5 cm layer of this organic material was mixed with mineral soil to a depth of 7.5 cm 

(fig. 3). Soil from the rooting zone of local transplants 

was the source for the inoculum. About 1.2 liters of 

soil were mixed with about 20 liters of water to make 

a slurry. Three liters of this slurry were sprinkled over 

each plot and raked into the soil. The final two plots 

were amended with compost in addition to the organic matter and inoculum treatment. We added 2.5 cm 

of commercially available compost (sewage sludge/log 

yard waste compost with a C:N of approximately 20:1; 

Ekocompost®, Missoula, Montana), lightly watered 

and raked into the top 10 cm of organic and mineral 

soil.

Figure 1. The appearance of the mulch blanket immediately 

after planting.

Figure 2. Distribution of treatments for one campsite, illustrating completely random assignment of treatments within mulch 

whole-plot units, as well as the separate non-scarified control. Treatments are: mulch or no mulch; seed or no seed; no soil 

amendment, organics amendment or organics and compost amendment; and scarified or not scarified.
USDA Forest Service RMRS-GTR-185. 2007 3

The two levels of planting were planted and unplanted. Within each whole plot, three plots were planted 

(seeded and transplanted) and three were not. Seeding 

involved (1) collecting seed locally from several species 

with mature seed, (2) dividing available seed into equal 

quantities for each seeded plot, (3) pinch-broadcasting 

seed over the plot, and (4) raking seed into the upper 

2.5 cm of soil. Seeded species varied between campsites depending on locally available plants with mature 

seed. Juncus parryi and Phleum alpinum (alpine timothy) were seeded on three of the campsites. Antennaria 

alpina (alpine pussytoes), Antennaria lanata (woolly 

pussytoes), and Sibbaldia procumbens (creeping sibbaldia) were seeded on two campsites. Aster alpigenus 

(alpine aster), Danthonia intermedia (timber oatgrass),

Penstemon globosus (globe penstemon), and Sitanion 

hystrix (bottlebrush squirreltail) were each seeded on 

one campsite. Locally available seed was unusually limited due to the unusually short growing season in 1995. 

One of the campsites (at Crescent Lake) was not seeded 

due to a lack of mature seed in the vicinity.

Transplanting involved (1) digging up enough transplants in the vicinity to plant equal numbers of each 

species in each plot, (2) digging a hole and placing transplants in the hole, along with Vita-start (vitamin B-1) 

to reduce transplant shock (fig. 4), and (3) giving each 

transplant 0.6 liters of water. Plots not planted were 

given an equivalent amount of water. Most transplant 

plugs were between 5 and 25 cm in diameter, and most 

plots received five to six plugs (fig. 5). Most plugs contained only one species, but some contained more than 

one. Transplanted species varied between campsites. 

Vaccinium scoparium and Juncus parryi were intentionally transplanted on five of the six campsites. Phyllodoce 

empetriformis, Carex rossii, Luzula hitchcockii

(smooth woodrush), and Sibbaldia procumbens were 

intentionally transplanted on two campsites. Species that 

were intentionally transplanted on only one campsite 

were Abies lasiocarpa, Achillea millefolium (yarrow),

Antennaria alpina, Antennaria lanata, Aster alpigenus, Calamagrosts canadensis (bluejoint reedgrass), 

Danthonia intermedia, Hypericum formosum (western St. John’s-wort), Oryzopsis exigua (little ricegrass), 

Pinus contorta, Polemonium pulcherrimum (showy polemonium), and Spiraea betulifolia (shiny-leaf spirea).

Thirteen other species were unintentionally included in 

plugs. Nomenclature follows Hitchcock and Cronquist 

(1973).

Seeding and transplanting occurred only in the central 1 m2

 of each plot. Measurements were also confined 

to this central area, leaving a 0.5 m buffer between the 

measured portion of each treated plot. In 1996, when it 

appeared that soils were extremely dry, plots were watered several times. We did this because reports from 

earlier campsite restoration projects in the Pacific 

Northwest indicated that it is common for most seedlings to die during prolonged periods of summer drought 

Figure 3. Application of soil amendments.

Figure 4. Planting a transplant.

Figure 5. Typical transplant cover and density immediately after planting.
4 USDA Forest Service RMRS-GTR-185. 2007

(Lester 1990). All plots were given an equal amount of 

water (about 2 liters per plot). No supplemental watering 

occurred in later years.

Climatic variability clearly influenced temporal patterns of plant response, primarily by determining the 

availability of soil moisture. Although there was yearly 

variation, growing season conditions generally became 

increasingly droughty over the 10-year study period. For 

the first 4 years of the study, the late snowpack was unusually deep, suggesting that early season conditions 

were much less droughty than normal. This was not the 

case for the final 6 years of the study. In 1996, the first 

growing season after restoration, when plots were occasionally irrigated, the summer was dry but cool. In 1997, 

the summer was cool and wet. In 1998, the summer was 

hot and dry, and plants were not given supplemental water. Long-term, regional drought set in with the hot, dry 

summer of 2000 and the generally low precipitation that 

fell throughout 2001. Drought persisted through 2005.

Measurements

We measured transplant survival and growth, seedling density and plant cover at least once every year for 

7 years (fig. 6). In addition, cover was assessed after 

10 years.

Transplants—For each transplant, we measured areal extent of canopy cover (using a 1 m square PVC 

frame with a 5 cm by 5 cm grid) and maximum height. 

Measurements were taken immediately after transplanting (September 1995) and in each September thereafter, 

for 7 years (through 2002).

Seedlings—Seedling establishment was assessed beginning in early July 1996. Every two weeks from early 

July to early September (four times), all established 

seedlings were mapped. Each seedling was identified by 

species, and a colored toothpick was placed next to it to 

denote date of establishment. This made it possible to 

assess period of establishment and death if mortality occurred. In 1997, seedlings that germinated in 1996 were 

identified on the basis of their size, location, and species. New seedlings (the 1997 cohort) were identified in 

the surveys conducted every two weeks. In some plots, 

seedlings were so numerous that they were assessed in 

subplots. In 1998, seedling assessment occurred twice, 

in mid-July and early September. In subsequent years 

(through 2002), we assessed the density of seedlings 

(plants that had established by seed since the beginning 

of the study) only in September.

Each year, 10 individuals of a seeded species were 

randomly selected on each plot, and their height was 

measured in September. In 1996 and 1997, we excavated 

four individuals of the same species that were growing 

within the treated plot, but outside the area where measurements were taken. Their root and shoot biomass was 

measured following cleaning and drying. In 1998, we 

measured the height of the tallest individual of the seeded species, which we found to be highly correlated with 

biomass. This avoided the need for further destructive 

sampling. In 1997 and 1998, height and biomass measurements were taken only on seedlings that germinated 

and established in 1996. In 1996 and 1997, transplant areal extent and seedling locations were digitized to allow 

spatial analysis.

Plant cover—Every September between 1996 and 

2002, total plant cover was ocularly estimated to the 

closest percent if cover was 10 percent or less and in 

10 percent increments thereafter. Total vegetation cover was assessed, as was the cover of each transplanted 

species and each species that had established from seed. 

Final cover estimates were taken in September 2005, 

10 years after seeding and transplanting.

Reference conditions—Total vegetation cover and 

the cover of individual species were estimated in undisturbed plots near to each restored campsite. The means 

from these six plots are used as targets for successful 

restoration.

Soil characteristics—Soils analyses were conducted 

twice during the study. Three years after the restoration 

treatments, soil samples were collected on each campsite 

from (1) plots that received the treatment of organics, inoculum, and compost, (2) untreated parts of the closed 

campsite, and (3) undisturbed sites adjacent to the campsites. Parameters assessed were: microbial biomass C, 

basal respiration rates, total organic carbon, total nitrogen, ammonium, potentially mineralizable nitrogen, and Figure 6. Quadrats used to assess plant cover, seedling density, and transplant growth.
USDA Forest Service RMRS-GTR-185. 2007 5

several indicators of the carbon utilization capabilities 

of the microbial community. Details of the laboratory 

analyses and results can be found in Zabinski and others 

(2002). In 2003, 8 years after the restoration treatments, 

soil samples were again taken on each campsite. As before, samples were taken from untreated parts of the 

closed campsite and from undisturbed sites adjacent 

to the campsites. This time, however, the effects of six 

different treatments were assessed: planted plots that 

received each of the three soil amendment treatments 

and unplanted plots that received each of the three soil 

amendment treatments. In each case, only plots that 

were not covered with the mulch mat were sampled. Soil 

analysis procedures were identical to those used 5 years 

earlier, except that carbon utilization capabilities were 

not investigated.

Data Analysis and Presentation

Some of the results of this study are presented in 

more detail elsewhere. Zabinski and others (2002) describe results of the early soils study. Cole and Spildie 

(2006) and Cole (in press) present detailed results for 

transplants and seedlings, respectively. In this report, 

results presented elsewhere are only briefly reviewed. 

Most attention is given to the effect of restoration on soil 

8 years after treatment and to how plant cover responded 

to treatment over the 10-year study period.

The soils data are analyzed using paired t-tests and 

univariate analyses of variance in SPSS 9.0. First we 

tested differences between untreated parts of the campsite and undisturbed control sites using paired t-tests. 

Then we tested the effects of the main factors, soil 

amendment, and planting on soil characteristics. Most 

data were square-root transformed to better comply 

with assumptions about normality. Where there were 

significant main effects, we assessed the significance 

of differences between means using Tukey’s honestly 

significant differences test, which adjusts for multiple 

comparisons. Then we assessed which treatments differed from the untreated campsite using Dunnett’s tests. 

Finally, we assessed which treatments differed from undisturbed controls, also using Dunnett’s tests.

For the cover data, we performed repeated measures analyses of variance, appropriate for split-plot 

designs (using an autoregressive covariance structure, 

PROC MIXED in SAS 9.1). Most data were squareroot transformed to better comply with assumptions 

about normality. In many cases, treatment effects varied 

significantly with time since treatment (in other words, 

interactions with time were significant). In these cases, 

we describe treatment effects for each of the 10 years 

of the experiment, but the significance of effects is only 

assessed at the end of the experiment, in 2005. In those 

cases where treatment interactions with time were not 

significant, we report results of the repeated measures 

analyses.

To assess the hypothesis that scarification has positive effects, the control (the plot that was not even 

scarified) was compared to the one plot on each campsite that was scarified but not mulched, amended, or 

planted. For the three factors included in the split plot 

design (mulch, soil amendment, and planting), main effects of each factor and interactions among factors were 

assessed. Interactions among the treatments were never 

statistically significant. Therefore, we simply report the 

main effects of treatments. We report ANOVA treatment 

effects when there are two treatments being compared 

(effects of scarification, planting, and mulch). For the 

soil amendments, we report Dunnett’s tests, adjusted for 

multiple comparisons, of differences between each of 

the two amendments and the non-amended treatment, as 

well as Tukey-Kramer tests, adjusted for multiple comparisons, of differences between the two amendments.

Results

Effects on Soils

Compared to undisturbed controls, unrestored campsite soils had significantly lower organic carbon (C), 

total nitrogen (N), ammonium (NH4), potentially mineralizable nitrogen (PMN), and microbial biomass (fig. 7). 

Basal respiration rates (an indicator of the magnitude of 

microbial populations) did not differ significantly. These 

results, based on soils collected in 2003, 8 years after 

the beginning of the experiment, are similar to those reported for soils collected in 1998 (Zabinski and others 

2002). In 1998, basal respiration rates did differ between 

campsites and controls if the soil on controls was collected immediately underneath vegetation, rather than 

in open areas between vegetation clumps. Zabinski and 

others (2002) also report that control sites had higher 

measures for an indicator of the functional diversity of 

microbial populations, the number of substrates metabolized in carbon utilization profiles.

Since camping reduced levels of most of these parameters, we hypothesized that soil amendments and 

planting might accelerate soil recovery and increase 

levels of these parameters. The soil amendments had 

much more pronounced effects on soil characteristics 

than whether or not plots were transplanted and seeded 
6 USDA Forest Service RMRS-GTR-185. 2007

(table 1). Compared to soil in plots that were only scarified, the soil in plots amended with organics and compost 

had significantly higher levels of organic C, total N, potentially mineralizable N, basal respiration rates, and 

microbial biomass (fig. 7). In the plots amended with organics only (no compost), soils had significantly higher 

levels of organic C and total N than on scarified plots 

and significantly lower levels of organic N, potentially 

mineralizable N, basal respiration rates, and microbial 

biomass than on organics and compost plots.

Plots amended with organic matter and compost differed significantly from untreated campsites for all 

parameters other than basal respiration. Moreover, plots 

amended with organics and compost were not significantly different from controls for any of these parameters. 

This suggests amendment with organics and compost 

Figure 7. Effect of restoration treatments on soil characteristics.
USDA Forest Service RMRS-GTR-185. 2007 7

was sufficient to ameliorate many of the effects of longterm camping on these soils, without exceeding levels 

found in undisturbed soils. Plots amended with organics only had soil characteristics that were consistently 

intermediate between those for untreated campsites and 

control sites. However, organics only plots differed significantly from untreated campsites only in organic C. 

They differed from controls only in potentially mineralizable N. Plots that were only scarified did not differ 

significantly from untreated campsites for any of these 

parameters. They differed from controls for all parameters other than NH4 and basal respiration.

For most of these parameters, the soil in plots that 

were transplanted and seeded was not significantly 

different from the soil in plots that were not planted. 

Contrary to our hypotheses, organic C was significantly lower on planted plots (6.5 percent) than it was on 

plots that were not planted (8 percent). Similarly, total N 

was significantly lower on planted plots (0.25 percent) 

than it was on plots that were not planted (0.28 percent). 

Neither of these differences seems substantial, but clearly planting alone does not lead to rapid recovery of soil 

properties.

Effects on Total Plant Cover

Following closure and restoration of the campsites, 

total plant cover increased from zero to 12 percent 

10 years later (table 2). Total cover reached a maximum 

of almost 15 percent in 1999 and declined somewhat 

thereafter. This response pattern was particularly 

pronounced on plots that were amended with organics 

and compost, suggesting that the effect of amendments 

was most dramatic in the first few years following treatment. The pattern was also more pronounced on planted 

plots, particularly for seeded species.

Total vegetation cover is still substantially below the 

50 percent cover that is typical of adjacent undisturbed 

vegetation. Initially, transplants accounted for most 

of the cover. After 10 years, however, the total cover 

of plants that germinated from seed—both intentionally seeded and volunteer (11 percent)—approximated 

that of transplants (12 percent) on plots that were planted. Similarly, seeded plants were initially much more 

abundant than plants that volunteered (plants that germinated from seed in the soil seedbank or that dispersed 

naturally onto the site). After 10 years, cover of volunteers was only slightly lower (5 percent) than cover of 

seeded plants (6 percent) on seeded plots. On plots that 

were not seeded and transplanted, volunteers accounted for all the vegetation cover. Non-native species were 

absent.

Treatment effects—Restoration treatments varied in 

effectiveness (fig. 8). Mere closure was not successful. 

On plots that were not scarified, mean cover never exceeded 1 percent and was only 0.4 percent 10 years after 

closure. Scarification alone was slightly more successful (fig. 9). Plant cover was significantly greater on plots 

that were scarified (but not seeded, amended with organics, or mulched) than on control plots that were closed 

Table 1. Analysis of variance results (F values) for the effect of soil amendments and planting on soil characteristics.

Source of variation df Organic C Total N NH4 PMN Respiration Biomass C

F

Soil amendment 2 14.7** 18.5** 0.2 5.5* 5.1* 3.6*

Planting 1 5.9* 7.1* 1.4 1.2 0.8 1.2

Interaction 2 1.8 2.0 0.2 2.3 0.3 1.5

Significance: *<0.05; **<0.01

Table 2. Variation in plant cover (percent) over the 10-year study.

 1996 1997 1998 1999 2000 2001 2002 2005

All plants (total cover) 8.0 7.2 13.3 14.7 12.1 9.7 9.4 12.4

Transplantsa 11.3 9.1 13.3 13.2 10.4 9.2 9.4 12.1

Seeded plantsa 5.6 5.2 9.9 10.8 9.5 6.0 4.7 6.3

Volunteer seedlingsb 1.6 2.4 4.9 6.5 5.3 3.9 4.0 4.7

a

 For transplants and seeded plants, cover is the mean of those plots that were planted.

b

 Volunteer seedlings cover is derived from all plant cover on unplanted plots, and from the cover of seedlings of 

species that were not seeded on planted plots.
8 USDA Forest Service RMRS-GTR-185. 2007

to use but received no restoration treatments (table 3). 

However, differences were small. 10 years after closure, 

mean plant cover on scarified-only plots was less than 3 

percent.

The planting (both transplanting and seeding) treatment had the most pronounced effect on plant cover 

(table 4). Magnitude of effect varied significantly with 

year since planting (that is, the interaction between 

planting and year was significant). Consequently, the 

significance of treatment effects was assessed at the end 

of the study, in 2005 (table 5). 10 years after planting, 

cover was more than three times greater on planted plots 

Figure 8. Variation in effectiveness of treatments 2 years after treatment.

Figure 9. Effect of scarification (but no other treatments) on 

plant cover.

Table 3. Effect of scarification on plant cover, repeated 

measures analysis of variance results.

Effect df F p

Scarification (S) 1 3.84 0.03*a

Year (Y) 7 0.50 0.83

Interaction (S*Y) 7 1.21 0.30

* Denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypothesis that cover would increase with 

scarification.

Table 4. Effects of planting, soil amendments, and mulching 

on plant cover, repeated measures analysis of variance 

results.a

Effect df F p

Planting (P) 1 186.4 <0.01*

Soil amendment (S) 2 6.6 <0.01*

Mulch (M) 1 0.1 0.83

P*S 2 2.4 0.12

P*M 1 0.2 0.69

S*M 2 0.6 0.56

Year (Y) 7 17.7 <0.01*

Y*P 7 5.4 <0.01*

Y*S 14 2.3 <0.01*

Y*M 7 1.8 0.10

* Denotes a statistically significant difference (α = 0.05). a

 Higher order interactions were not significant and are not shown.
USDA Forest Service RMRS-GTR-185. 2007 9

(19 percent) than on plots that were not planted (6 percent) (fig. 10).

Soil amendments were also effective, but to a lesser 

degree (table 4). Again, magnitude of effect varied with 

year since treatment, being least pronounced in the first 

years following closure (fig. 11). 10 years after treatment, plant cover on plots that received organics and 

compost amendments was significantly greater than on 

plots that received no amendments (adjusted Dunnett’s 

multiple comparison, t = 3.34, p = 0.01). The plant cover 

on plots that were amended with organics only appeared 

greater than on plots that received no amendments, but 

differences were not statistically significant (adjusted Dunnett’s multiple comparison, t = 1.41, p = 0.16). 

Differences between the organics and compost and organics only plots were also not statistically significant 

(adjusted Tukey-Kramer multiple comparison, t = 1.93, 

p = 0.09).

Mulching with a biodegradable mat did not have a 

significant effect on plant cover, over the entire length 

of the study (table 4), for 2005 (table 5), or for any other 

year (fig. 12).

Effects on Transplant Cover

Transplants differed from plants that grew from seed, 

both in temporal patterns of response and in the effectiveness of the restoration treatments. Although there 

was annual variation, the total cover of transplants after 

10 years was comparable to their cover immediately after transplanting (fig. 13). As reported in detail in Cole 

and Spildie (2006), this temporal pattern resulted from 

growth in transplant size offsetting the mortality of individual transplants. In the first 7 years of the study, 32 

percent of the transplants died; however, the mean area 

of survivors increased 39 percent.

Growth forms varied in response. The cover of small 

trees increased most, where they were planted, while 

the cover of shrubs decreased most (fig. 13). As Cole 

and Spildie (2006) report, most planted trees (79 percent) survived, and the size of the trees increased greatly 

(mean increase in area of 243 cm2). Graminoids survived 

Table 5. Effects of planting, soil amendments, and mulching 

on plant cover in 2005.

Effect df F p

Planting (P) 1 79.5 <0.01*a

Soil amendment (S) 2 5.6 0.01*a

Mulch (M) 1 3.3 0.13a

P*S 2 0.4 0.65

P*M 1 0.1 0.74

S*M 2 0.0 0.98

* Denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypotheses that cover would increase with 

treatment.

Figure 10. Effect of planting on plant cover.

Figure 11. Effect of soil amendments on plant cover.

Figure 12. Effect of mulching on plant cover.
10 USDA Forest Service RMRS-GTR-185. 2007

most frequently (87 percent); they also grew substantially (mean of 56 cm2

). Forbs survived less frequently 

(72 percent) and grew more modestly (mean of 56 cm2). 

Shrubs, in contrast, had poor survivorship (45 percent) 

and experienced little growth (mean increase in area of 

0 cm2).

Treatment effects—Beyond closure and transplanting, other restoration treatments had relatively little 

effect on plant cover. Mulch had no effect on transplant 

cover (table 6). Transplant cover did vary significantly 

among the soil amendments and there was no interaction 

between year and treatment (table 6). Overall, transplant 

cover on plots amended with organics and compost was 

significantly greater than on plots that were only scarified (adjusted Dunnett’s multiple comparison, t = 2.46, 

p = 0.03). As Cole and Spildie (2006) report, amendments increased transplant growth rates but not survival. 

During the period of time between about two and 6 years 

after transplanting, it was possible to visually identify 

the composted plots by the large stature of many of the 

transplants. However, the magnitude of effect declined 

toward the end of the 10-year study (fig. 14). In 2005, 

plots amended with organics and compost did not have 

significantly more transplant cover than plots that were 

only scarified (adjusted Dunnett’s multiple comparison, 

t = 0.89, p = 0.31) and these plots could no longer be easily identified visually, on the basis of transplant stature.

Graminoids were the only growth form for which 

transplant cover was significantly higher on organics 

and compost plots than on unamended plots (adjusted Dunnett’s multiple comparison, t = 2.49, p = 0.04). 

Cole and Spildie (2006) report that graminoid transplant growth was also greatest on organics and compost 

plots.

Responses of individual species—Despite small 

sample size, some insight into the variable response of 

individual species can be gained (table 7). All seven of 

the Achillea millefolium transplants died. Otherwise, 

survivorship varied between 43 percent and 100 percent. 

Note that because only transplant cover was assessed 

in 2005, survivorship and change in size of individual 

transplant can only be estimated through 2002. Of the 

most abundant species, survivorship was notably high 

(100 percent) for Juncus parryi and Carex rossii. It was 

notably low for Vaccinium scoparium (45 percent) and

Phyllodoce empetriformis (50 percent).

Of the eighteen species that survived to 2002, eight 

species grew substantially (increase in area of more 

than 20 percent), while six species declined substantially in size. The net effect of survivorship and growth 

is reflected in cover values in table 7. Cover increased 

over the 10-year period for nine species and decreased 

for 10 species. The species that increased most were 

trees and graminoids: Pinus contorta, Abies lasiocarpa, 

Calamagrostis canadensis, Juncus parryi, and Carex 

rossii. The species that decreased most were Vaccinium 

Figure 13. Change in cover of transplants since transplanting: 

all plants and growth forms.

Table 6. Effects of soil amendments and mulching on transplant 

cover, repeated measures analysis of variance results.

Effect df F p

Soil amendment (S) 2 3.0 0.05*a

Mulch (M) 1 0.3 0.60

S*M 2 0.3 0.74

Year (Y) 7 8.8 <0.01*

Y*S 14 0.6 0.87

Y*M 7 1.4 0.20

* Denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypothesis that cover would increase with 

treatment.

Figure 14. Effect of soil amendments on transplant cover.
USDA Forest Service RMRS-GTR-185. 2007 11

scoparium, Phyllodoce empetriformis, Danthonia intermedia, Aster alpigenus, and Achillea millefolium.

For the species that transplanted successfully, plants 

survived and grew well whether soils were amended 

or not. Nevertheless, in the case of both Juncus parryi 

and Carex rossii, growth rates were significantly greater 

on plots amended with either organics or organics and 

compost, in comparison to unamended plots (Cole and 

Spildie 2006).

Of the species that transplanted least successfully, it 

was possible to assess the effect of soil amendments on 

Vaccinium scoparium and Phyllodoce empetriformis. 

Soil amendments had little effect on the transplanting 

success of P. empetriformis. For V. scoparium transplants, soil amendments affected transplant survival but 

not growth (fig. 15). Survival was substantially greater on plots that received either of the soil amendment 

treatments, starting the fourth year following transplanting. Although differences between treatments were not 

significant when the entire length of the experiment is 

examined (Wilcoxon chi-square = 2.37, p = 0.15), they 

were significant in 2002 (Pearson chi-square = 4.62, 

p = 0.05), the last year transplants were counted. Despite 

increased survivorship, mean cover of V. scoparium

transplants in 2005 was not significantly greater on organics and compost plots (2 percent) than on unamended 

plots (1.3 percent) (adjusted Dunnett’s multiple comparison, t = 0.56, p = 0.17)

Effects on Seedling Cover

In contrast to the total cover of transplants, the cover 

of plants that grew from seed (seedlings) doubled over 

10 years (fig. 16). However, this increase was not consistent. Seedling cover increased almost threefold in the 

first 4 years following closure, declined substantially 

for the next 3 years and then increased slightly between 

2002 and 2005. Both seeded species and volunteers exhibit this temporal pattern of response, although the 

increase in cover of volunteers has been more slow and 

steady. Cover of seeded species after 10 years was only 

Table 7. Responses of individual transplanted species.

Survivalb Survivor area (cm2

) Coverd (%)

Species Numbera (%) 1995 2002 1996 2005

Abies lasiocarpa 8 63 66 121 1.1 1.6

Achillea millefolium 7 0 - - 1.3 0.0

Antennaria alpina 8 50 117 41 1.0 0.1

Antennaria lanata 13 92 90 80 1.4 1.3

Aster alpigenus 8 100 76 19 2.0 0.5

Calamagrostis canadensis 7 86 144 142 0.7 3.3

Carex rossii 21 100 122 223 2.0 2.9

Danthonia intermedia 9 89 123 57 2.6 0.6

Festuca viridula 5 80 141 155 2.0 2.3

Hypericum formosum 8 50 174 46 1.1 0.3

Juncus parryi 40 100 199 278 2.6 4.0

Luzula hitchcockii 17 47 173 138 1.1 0.8

Oyzopsis exigua 6 100 227 198 2.2 1.5

Phyllodoce empetriformis 16 50 154 235 3.2 1.7

Pinus contorta 6 100 66 471 1.0 11.0

Polymonium pulcherrimum 6 83 64 164 0.6 1.2

Sibbaldia procumbens 18 89 125 220 1.9 2.3

Spiraea betulifolia 7 43 50 30 0.6 0.8

Vaccinium scoparium 69 45 135 114 3.1 2.0

a

 Number of individuals of each species that were originally transplanted.

b

 Percentage of original transplants that survived until 2002.

c

 Mean area of those original transplants that survived, in 1995 and 2002.

d

 Mean cover of all plots transplanted with the given species.

Figure 15. Effect of soil amendments on survivorship of 

Vaccinium scoparium.
12 USDA Forest Service RMRS-GTR-185. 2007

slightly greater than it was the first summer after seeding. Cover of volunteers was three times greater in 2005 

than it was in 1996. In 1996, the cover of seeded species on plots that were seeded was 3.5 times the cover 

of volunteer species. In 2005, cover of seeded species 

was only 1.3 times the cover of volunteers. As reported 

in detail in Cole (in press), the density of seeded species 

was greatest in 1996, while the density of volunteers 

was greatest in 1998. Consequently, increases in cover 

reflect increases in the size of seedlings that more than 

offset seedling mortality.

Most seedling cover is provided by graminoids, while 

shrub and tree seedling cover is minimal (fig. 17). This 

partially reflects the fact that shrub and tree species 

were not seeded and that only graminoids were seeded on two of the sites. But graminoids and forbs were 

also the most abundant volunteer seedlings. Both graminoids and forbs increased in cover over the 10 years, but 

cover of tree seedlings declined. Although the cover of 

what we called shrub seedlings increased, many of these 

“seedlings” may have sprouted from roots rather than 

reproduced from seed. Consequently, we are hesitant to 

try to describe the response of shrub seedlings beyond 

noting that they remain negligible, even 10 years after 

closure. The variable temporal pattern of increasing cover is largely explained by the response of graminoids.

Only one non-native individual established on these 

plots, and it only survived for two seasons. Non-native 

species are largely absent at the elevation where these 

campsites are located; they are abundant along trails and 

on campsites at lower elevations (below 2000 m).

Treatment effects—Scarification had a small but 

positive effect on seedling cover. As noted earlier, plant 

cover on plots that were only scarified (all seedlings) was 

significantly greater than on plots that were not scarified. 

Cole (in press) reports that 7 years after closure, plant 

density on scarified plots was more than three times the 

density on plots that were not scarified. In terms of cover, however, the magnitude of difference was never more 

than a couple percent.

The more elaborate treatments varied substantially in 

effect. Application of the biodegradable mulch mat did 

not have a clear effect on the cover of seedlings. In contrast, seeding had a pronounced effect (table 8). Although 

magnitude of effect declined somewhat over the 10-year 

study, seeded plots had two times more seedling cover in 

2005 than plots that were not seeded (fig. 18).

Results are less conclusive regarding the effect of 

planting treatments on the cover of volunteer seedlings. One might expect either increased success for 

volunteers on plots with transplants due to facilitation 

Figure 16. Change in seedling cover since campsite closure 

and seeding.

Figure 17. Change in seedling cover of different growth forms 

since campsite closure.

Table 8. Effects of seeding, soil amendments, and mulching 

on seedling cover, repeated measures analysis of variance 

results.a

Effect df F p

Seeding (SD) 1 28.3 <0.01* b

Soil amendment (S) 2 3.8 0.03* b

Mulch (M) 1 0.0 0.92

SD*S 2 0.4 0.69

SD*M 1 0.4 0.55

S*M 2 0.8 0.47

Year (Y) 7 14.9 <0.01* b

Y*SD 7 1.6 0.15

Y*S 14 2.4 <0.01*

Y*M 7 0.7 0.65

* Denotes a statistically significant difference (α = 0.05). a

 Higher order interactions were not significant and are not shown.

b

 One-tailed test of hypothesis that cover would increase with 

treatment.
USDA Forest Service RMRS-GTR-185. 2007 13

(remember that seeded plots were also transplanted) or 

decreased success due to competition. Volunteer cover 

was consistently higher on plots that were not seeded, 

starting the third year after closure (fig. 19). However, 

this difference was not statistically significant over the 

entire length of the study (repeated measures analysis 

of variance, F = 1.95, p = 0.24) or in 2005 (univariate 

analysis of variance, F = 0.37, p = 0.57). Therefore, we 

cannot confidently conclude that planting decreased the 

cover of volunteer species. However, we also cannot be 

confident that planting does not have an adverse effect, 

given the results illustrated in figure 19. More detailed 

examination of the data indicates that volunteer cover 

was much higher on unplanted plots on only two of the 

campsites. Cole (in press) reported that the density of 

volunteers did not differ between planted and unplanted plots, suggesting that if there is an adverse effect of 

planting on volunteers, it is a reduction in size rather 

than density of plants.

Amending soils also had a positive effect on seedling 

cover. The effectiveness of soil amendments varied over 

the course of the study (fig. 20), being least effective in 

the early years and most effective 4 or 5 years after treatment. Because the interaction with year since treatment 

was statistically significant (table 8), soil amendment effects are only evaluated in 2005, the final year of the 

study (table 9). In 2005, mean seedling cover on plots 

with organics and compost amendments was almost three 

times the seedling cover of unamended plots (adjusted Dunnett’s multiple comparison, t = 2.37, p = 0.03). 

Cover on plots with the organics only treatment was not 

significantly different from either unamended plots (adjusted Dunnett’s multiple comparison, t = 1.06, p = 0.13) 

or the organics and compost plots (adjusted TukeyKramer multiple comparison, t = 1.31, p = 0.20).

Responses of different species—Both seeded species 

and volunteers responded positively to the organics and 

compost soil amendment (table 10). Generally, graminoids and forbs responded positively to soil amendments, 

while tree seedlings did not (table 10).

Of the seeded species, only Sitanion hystrix did not 

establish well initially. It established at low densities 

Figure 18. Effect of planting on seedling cover.

Figure 19. Effect of planting on cover of volunteers.

Figure 20. Effect of soil amendments on seedling cover.

Table 9. Effects of seeding, soil amendments, and mulching 

on seedling cover in 2005.

Effect df F p

Seeding (SD) 1 27.7 <0.01*a

Soil amendment (S) 2 2.8 0.05*a

Mulch (M) 1 0.6 0.50

SD*S 2 0.5 0.59

SD*M 1 0.3 0.61

S*M 2 0.4 0.67

* Denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypotheses that cover would increase with 

treatment.
14 USDA Forest Service RMRS-GTR-185. 2007

on only two of six seeded plots and was absent on all 

plots 10 years later (table 11). The two additional seeded grasses, Danthonia intermedia and Phleum alpinum, 

established in abundance initially, but provided minimal 

cover 10 years later. D. intermedia survived on only one 

of six seeded plots, while P. alpinum survived on 10 of 

18 seeded plots. Neither of these species is well represented in the undisturbed adjacent vegetation, however.

In contrast, the two most common graminoids in the 

undisturbed vegetation, Juncus parryi and Carex rossii, 

increased in cover over the 10-year period (table 11). J. 

parryi was seeded on three of the campsites. It volunteered on all campsites and on 38 of the 54 plots where it 

was not seeded. Although the density of seeded J. parryi 

declined from a maximum of 251 seedlings in 1996 to 

only 36 seedlings in 2002 (as reported in Cole in press), 

mortality was more than offset by growth of those plants 

that survived. 10 years after treatment, J. parryi seedling cover on seeded plots was 4 percent. Along with the 

4 percent cover of J. parryi transplants, total cover of 

this species exceeded its mean cover of 6 percent in undisturbed vegetation within several years. On sites that 

were not seeded or transplanted, mean J. parryi cover 

was 1.1 percent. Although J. parryi transplants responded positively to soil amendment and Cole (in press) 

reports that the density of J. parryi seedlings was higher 

on amended soils, the cover of J. parryi seedlings did 

not vary significantly among soil amendments (repeated measures analysis of variance, F = 0.22, p = 0.81). In 

2005, the mean cover of J. parryi seedlings was 2.6 percent on unamended plots, 1.9 percent on organics plots, 

and 3.6 percent on organics and compost plots.

Carex rossii volunteered on 69 of the 72 plots that 

were at least scarified. Within 3 years, C. rossii cover exceeded the 1 percent cover typical of undisturbed 

sites. 10 years after closure, mean C. rossii cover was 

3.1 percent. C. rossii cover responded positively to both 

soil amendments. In 2005, mean cover of C. rossii was 

1.2 percent on non-amended plots, 3.2 percent on organics plots, and 4.7 percent on organics and compost 

plots (adjusted Dunnett’s multiple comparison, t = 2.18, 

p = 0.05 for the difference between non-amended and 

organics plots and t = 3.37, p < 0.01 for the difference 

between non-amended and organics and compost plots). 

Differences between organics and organics and compost 

plots were not statistically significant (adjusted Tukey’s 

multiple comparison, t = 1.17, p = 0.25).

Forbs responded less variably. Aster alpigenus and 

Sibbaldia procumbens both established in modest numbers on virtually all the plots on which they were seeded. 

Density of these species has declined precipitously 

(Cole in press), but cover in 2005 is still about 50 percent of their maximum cover (reached the first year after 

seeding) and not different from typical cover on undisturbed sites. Antennaria alpina and Penstemon globosus 

established in much greater abundance and, despite declining density, have increased in cover over the 10 

years. Although sample size is too small for statistical 

analysis, both of these species appear to have responded 

Table 11. Mean cover (percent)a at the end of each growing season for seeded species and the most abundant 

volunteers.

1996 1997 1998 1999 2000 2001 2002 2005

Antennaria alpina—seeded (n=12) 2.0 0.9 1.5 2.2 3.0 3.4 3.0 4.9

Antennaria alpina—volunteer (n=5) 0.2 0.4 0.6 0.7 1.0 1.4 2.3 2.1

Antennaria lanata—seeded (n=6) 0.4 0.4 0.3 0.9 0.5 1.1 0.7 1.5

Aster alpigenus—seeded (n-6) 0.7 0.5 0.5 0.5 0.5 0.5 0.5 0.3

Danthonia intermedia—seeded (n=6) 1.8 1.4 0.5 0.6 0.3 0.5 0.3 0.1

Juncus parryi—seeded (n=17) 1.3 1.6 2.9 3.6 3.3 2.7 2.6 4.1

Juncus parryi—volunteer (n=37) 0.3 0.4 0.7 1.0 1.0 0.7 0.9 1.1

Penstemon globosus—seeded (n=6) 3.7 2.3 4.6 7.4 5.6 6.4 5.1 8.2

Phleum alpinum—seeded (n=18) 4.3 4.7 10.7 9.9 8.2 2.3 1.1 0.1

Sibbaldia procumbens—seeded (n=11) 0.6 0.5 0.5 0.5 0.5 0.5 0.4 0.3

Sitanion hystrix—seeded (n=2) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.0

Carex rossii—volunteer (n=69) 0.5 1.0 2.7 3.3 2.5 2.2 2.2 3.1

a

 Mean cover on plots where the species established (n).

Table 10. Mean (s.e.) seedling cover in 2005, 10 years after 

treatment, on plots with various soil amendments.

Soil amendment

Organics 

None Organics and compost

Seeded species 2.7 (1.3) 5.1 (2.3) 11.2 (4.5) a

Volunteers 3.0 (0.7) 4.4 (0.7) 6.7 (1.4) a

Graminoids 2.9 (0.7) 4.2 (0.8) a 7.9 (1.6) a

Forbs 0.4 (0.2) 1.6 (0.9) 3.8 (1.4) a

Tree seedlings 0.5 (0.1) 0.4 (0.1) 0.3 (0.1)

a

 Treatments that differ significantly from untreated plots.
USDA Forest Service RMRS-GTR-185. 2007 15

favorably to the soil amendments. In 2005, mean cover 

of A. alpina was 0.6 percent on non-amended plots, 2 

percent on organics plots, and 5.5 percent on organics 

and compost plots. In 2005, mean cover of P. globosus 

was 0.5 percent on non-amended plots, 6.2 percent on 

organics plots, and 15.0 percent on organics and compost plots (fig. 21). Antennaria lanata established at 

more modest densities but also increased in cover. It 

also appears to have responded favorably to soil amendments. In 2005, mean cover of A. lanata was 0.5 percent 

on non-amended plots, 1.2 percent on organics plots, 

and 1.4 percent on organics and compost plots.

Seedling Establishment and Mortality

Additional insights into seedling response to restoration can be gleaned from the more frequent and detailed 

assessments of seedlings that were conducted the first 

3 years following restoration. Seedlings became established throughout the two-month assessment period 

(early July to early September), but two-thirds of the 

seedlings became established (cotyledons were welldeveloped) in early August—about one month after 

snowmelt. On seeded plots, the number of newly established seeded species declined greatly each year, from 

521/m2 the first year, to 159/m2 the second year and 

44/m2 the third year (fig. 22). The number of newly established volunteers declined from 30/m2

 the first year, 

to 24/m2 the second year, and 18/m2 the third year.

Mortality rates during the growing season, once 

seedlings were established (had well-developed cotyledons), were very low for the first two seasons (less 

than 1 percent for seeded species and 5 to 12 percent for 

volunteers) (fig. 22). Overwinter mortality rates were 

higher (22 to 33 percent for seeded species and 15 to 42 

percent for volunteers). Mortality of seeded species was 

much higher during the third growing season (45 percent), 

the first hot, dry summer without supplemental watering 

(supplemental watering occurred the first summer; the 

second summer was cool, with frequent precipitation). 

Mortality of volunteers during the third growing season 

was also higher than in early years but much less than for 

seeded species (22 percent). Only 33 percent of the established seedlings of seeded species survived three growing 

seasons, while 53 percent of the established seedlings of 

volunteers survived. Consequently, the proportion of 

seedlings that were volunteers increased from 5 percent 

after the first growing season to 14 percent at the end of 

the third growing season. This proportion had increased 

to 20 percent after 7 years.

For the first three seasons it was possible to distinguish treatment effects on seedling establishment rates 

from effects on mortality rates. In each of the first three 

seasons, the number of seedlings that established was 

much greater on seeded plots than on plots that were not 

seeded (table 12 and fig. 22), but neither the mulch nor 

the soil amendments affected natality rates.

Figure 21. Abundunt large Penstemon globosus seedlings 

on plot amended with organics and compost, 6 years after treatment.

Figure 22. Seedling density (#/m2, in squares) and survival 

rates (in triangles) of seeded species and volunteers from 

cohorts of seedlings that established in 1996, 1997, and 

1998. Densities are for early and late summer of each year 

and survival for intervening periods.
16 USDA Forest Service RMRS-GTR-185. 2007

As noted before, mortality rates were generally low 

the first two seasons. Mortality rates were significantly 

higher on plots that were not planted for the first 2 years 

(table 13), reflecting the fact that mortality rates were 

higher for volunteers than for seeded species those years 

(fig. 22). In 1998, however, the summer was hot and 

dry and plants were not watered. Mortality rates were 

much higher that summer (fig. 22). Under these conditions, seeded plots experienced much greater mortality 

(33 percent) than plots that were not seeded (17 percent) 

(tables 13 and 14). Higher mortality on seeded plots did 

little to offset the greater establishment rate on seeded 

plots. Seedling density on seeded plots was more than 

five times the density on non-seeded plots after three 

growing seasons (Cole in press).

Plots amended with organics and compost experienced much lower mortality rates (13 percent) than 

plots amended with organics only (23 percent) and 

plots without amendments (33 percent) (table 13 and 

14). As reported by Cole (in press), seedlings growing in plots amended with organics and compost grew 

much more rapidly than seedlings that did not receive this treatment. Both root and shoot biomass of 

seedlings was significantly greater in plots amended 

with organics and compost, both in 1996 and in 1997 

(table 15).

Table 12. Effects of seeding, soil amendments, and mulching on seedling natality (density of 

newly established seedlings) in each of the first three years after treatment.

1996 1997 1998

Effect df F p F p F p

Seeding (SD) 1 16.4 <0.01* 3.5 0.03*a 8.9 <0.01*

Soil amendment (S) 2 0.6 0.57 0.5 0.59 0.7 0.50

Mulch (M) 1 0.4 0.53 0.9 0.34 0.2 0.63

SD*S 2 1.0 0.38 0.3 0.76 1.1 0.35

SD*M 1 0.5 0.50 0.1 0.80 0.6 0.46

S*M 2 1.3 0.28 0.6 0.54 0.7 0.50

* Denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypothesis that nataility would increase with treatment.

Table 13. Effects of seeding, soil amendments, and mulching on seedling mortality in each 

of the first 3 years after treatment.

1996 1997 1998

Effect df F p F p F p

Seeding (SD) 1 5.4 0.02* 6.5 0.01* 4.7 0.04*

Soil amendment (S) 2 0.2 0.83 2.3 0.10 2.9 0.03*a

Mulch (M) 1 1.0 0.32 0.0 0.86 1.6 0.20

SD*S 2 0.1 0.92 1.3 0.29 0.1 0.92

SD*M 1 0.2 0.63 0.0 0.87 0.2 0.63

S*M 2 0.4 0.64 0.0 0.99 1.1 0.34

* Denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypothesis that mortality would decrease with treatment.

Table 14. Mean (s.e.) percent mortality of seedlings in each of the first 3 years after treatment.

Soil amendment Seeding treatment

Organics and

None Organics compost Not seeded Seeded

1996 13(3) 14(4) 12(4) 16(3) 8(2) a

1997 14(5) 3(3) 12(6) 14(4) 3(1) a

1998 33(7) 23(4) 13(3) a 17(3) 32(6) a

a

 Treatments that differ significantly from untreated plots.
USDA Forest Service RMRS-GTR-185. 2007 17

Because we mapped all seedlings that established for 

the first 2 years, it was also possible to assess the effect 

of transplants on seedling establishment and survival. 

As noted earlier, the density of volunteers on transplanted plots was not significantly different from density on 

plots that were not planted. This suggests that transplants have little effect on seedling establishment and 

survival, either positive or negative. To explore relationships further, we compared seedling density within 

the canopy of transplants to density outside the canopy. 

Two years after seeding, seedling densities were significantly lower within the canopy (paired t-test, t = 2.35, 

p < 0.01). We then assessed whether seedlings tended to 

establish close to, or far from, transplants. This was accomplished by calculating the distance from seedlings 

to the nearest transplant, as well as the mean distance 

from 100 random points to the nearest transplant. The 

differences between these distances was calculated and 

averaged. On average, seedlings were located 1.1 cm 

closer to transplants than expected, but this difference 

was not statistically significant (one-sample t-test, t = 

1.72, p = 0.10).

Effects on Species Richness

10 years after treatment, the mean 1 m2 plot had four 

species. At the scale of the entire campsite, mean species 

richness for the six closed campsites was 13 species. 

This is comparable to the mean of 15 species found on 

undisturbed reference sites. Treatments varied greatly 

in their effectiveness in restoring species richness. Plots 

that were scarified (but not treated in any other way) had 

significantly more species (mean of 1.8 species, s.e. = 

0.5) than plots that were not scarified (mean of 0.7 species, s.e. = 0.3) (one-tailed t-test, t = 1.83, p = 0.05). 

Of the more elaborate treatments, only planting was effective in increasing species richness (table 16). At the 

plot level of analysis, mean (s.e.) species richness was 

2.2 (0.5) species on unplanted plots and 6.3 

(0.4) species on planted plots. At the campsite level of analysis, species richness was 

5.0 (0.7) species on unplanted plots and 11.2 

(1.4) species on planted plots.

Progress in Relation to Reference 

Conditions

Clearly, progress has been made in restoring both the soil and vegetation on these 

campsites. However, degree of progress varied among treatments and among sites, as well as among 

the measures of progress that we employed. To assess 

progress, it is helpful to compare conditions on the 

closed campsites to campsite conditions prior to campsite closure and to reference conditions on undisturbed 

control sites.

As illustrated in figure 7, amendment of campsite soil 

with organics and compost resulted in near-complete restoration of the soil characteristics we examined. Soils on 

these plots did not differ significantly from undisturbed 

controls, while all characteristics were higher than on unrestored portions of the campsite. In contrast, plots that 

were scarified only showed little recovery. Soils on these 

plots generally differed significantly from undisturbed 

controls and were not different from soils on unrestored 

portions of the campsite. Plots amended with organics 

only were intermediate, but more similar to those that 

were scarified only. It is important to remember, however, that if we had assessed physical characteristics of 

the soil (such as porosity or infiltration rates), both degree of progress and the relative success of the different 

treatments might be different.

The 12 percent mean vegetation cover on campsites, 

10 years after closure, represents substantial progress in 

vegetation recovery compared to the 0 percent cover that 

typified these campsites prior to closure. However, vegetation cover is still far from the 50 percent cover that is 

Table 15. Root and shoot biomass, mean (s.e.) on plots with different soil 

amendment treatments.

Soil amendment

Organics and

None Organics compost

1996 root biomass (mg) 1.7 (0.3) 1.9 (0.4) 3.4 (0.7) a

1996 shoot biomass (mg) 3.7 (1.1) 6.1 (1.6) 8.6 (2.0) a

1997 root biomass (mg) 30 (14) 38 (3) 112 (29) a

1997 shoot biomass (mg) 71 (42) 62 (18) 231 (66) a

a

 Amended plots that differed significantly from non-amended plots.

Table 16. Effects of planting, soil amendments, and mulching 

on species richness in 2005.

Effect df F p

Planting (P) 1 87.7 <0.01*a

Soil amendment (S) 2 0.5 0.32a

Mulch (M) 1 0.3 0.30a

P*S 2 0.2 0.79

P*M 1 0.1 0.71

S*M 2 0.2 0.81

* denotes a statistically significant difference (α = 0.05). a

 One-tailed test of hypotheses that richness would increase with 

treatment.
18 USDA Forest Service RMRS-GTR-185. 2007

typical of undisturbed sites. Progress varied both among 

campsites and among treatments. On plots that were given the most effective treatments (scarified, planted, and 

amended with organics and compost), mean cover after 

10 years was 27 percent, about one-half of the cover of 

reference sites. On one of the campsites, plots that were 

given this treatment were at 50 percent cover after 10 

years (fig. 23).

In addition to interest in increasing vegetation cover, 

we were also interested in restoring vegetation similar 

in composition to undisturbed conditions. As illustrated in table 17, most of the vegetation on the closed 

campsites was herbaceous. This contrasts sharply with 

composition of the groundcover on undisturbed sites. 

Shrubs accounted for 57 percent of the cover on undisturbed sites but only about 11 percent of the cover on the 

campsites in 2005 (fig. 24). In the undisturbed vegetation, graminoids accounted for 26 percent of the cover; 

on the campsites they accounted for 65 percent of the 

cover. Finally forbs made up 17 percent of the cover of 

undisturbed vegetation and 24 percent of the cover on 

campsites. Campsite composition was most similar to 

reference conditions immediately after the restoration 

treatments (table 17 and fig. 24). Dissimilarity increased 

to a maximum in 1999, when total cover also peaked, 

and has declined since.

Most treatments were not beneficial in restoring 

the native species composition. Transplanting was the 

only effective way of establishing shrubs on the sites. 

However, even on plots that were planted and received 

the organics and compost treatment, the vegetation was 

12 percent shrubs, 53 percent graminoids, and 35 percent forbs. Shrubs comprised about 40 percent of the 

vegetation cover on planted plots on two of the campsites (fig. 25), but were virtually absent on two of the 

other sites.

Of the 13 species with a mean cover of more than 

0.1 percent on undisturbed sites, only Carex rossii, 

Antennaria alpina, and Sibbaldia procumbens had similar cover levels when all treatments are included (table 

18). On plots that were planted and amended with organics and compost, Juncus parryi, Pinus contorta,

and Luzula hitchcockii also were surviving at levels 

at least equal to those on reference sites. In contrast, 

even on transplanted and composted sites, Vaccinium 

Figure 23. Plot that was planted and amended with organics 

and compost, with 50 percent cover after 7 years.

Table 17. Variation in cover of different growth forms on campsites over the 10-year study.

1996 1997 1998 1999 2000 2001 2002 2005

Graminoids 4.6 5.3 10.2 12.5 10.1 6.9 6.9 7.9

Forbs 3.3 2.1 2.9 3.0 2.7 2.8 2.3 2.9

Shrubs 2.0 2.1 1.8 1.4 1.0 0.8 0.9 1.4

Trees 0.6 0.6 0.8 0.6 0.6 0.6 0.7 1.4

Figure 24. Relative cover of growth forms on closed campsites and undisturbed control sites.
USDA Forest Service RMRS-GTR-185. 2007 19

scoparium and Phyllodoce empetriformis had mean 

cover of 2.5 percent and 0.4 percent, respectively. 

On reference sites, these species have mean cover of 

27 percent and 7.1 percent, respectively. Of the less 

common species, planting resulted in coverages that 

exceeded those on reference sites for all species other than Gaultheria humifusa, Achillea millefolium, and

Sitanion hystrix (table 18).

Forty-one different species appear to have volunteered on closed campsites (table 19). However, as many 

as 10 of these species may be incorrectly classified as 

volunteers, either because they were overlooked in transplanted plugs or because they sprouted from roots of 

established plants. About half of the species that volunteered were species that we planted on the sites. Twenty 

species volunteered only on closed campsites.

On average, we transplanted and/or seeded six or seven different species on each campsite. After 10 years, the 

mean number of species growing on campsites was 13. 

This level of species richness is close to the mean of 15 

species growing on undisturbed control sites.

Discussion

The treatments we applied to these highly disturbed 

campsites were partially successful in restoring these 

sites. There has been significant progress in soil and 

vegetation recovery, particularly on those plots that 

were planted and amended with organics and compost. 

Some soil impacts have also been mitigated. Vegetation 

Figure 25. Unusually luxuriant growth of Vaccinium scoparium

and Phyllodoce empetriformis transplants after 7 years.

Table 18. Mean percent cover of planted species on all campsite plots, plots that were planted and amended 

with organics and compost, and undisturbed reference sites.

Number Planted and 

Species of camps All treatments composted Undisturbed

Vaccinium scoparium 5 1.0 2.5 27.0

Phyllodoce empetriformis 3 0.4 0.4 7.1

Juncus parryi 6 3.1 6.2 5.2

Abies lasiocarpa 4 0.4 0.5 4.1

Pinus contorta 4 1.0 1.8 1.7

Carex rossii 6 2.6 5.2 1.5

Antennaria lanata 3 0.3 0.8 1.4

Antennaria alpina 2 0.9 2.8 0.8

Festuca viridulaa 2 0.1 0.3 0.8

Veronica cusickiia 3 0.1 0.1 0.8

Sibbaldia procumbens 3 0.5 1.8 0.5

Gaultheria humifusaa 0 0 0 0.4

Luzula hitchcockii 2 0.2 0.3 0.3

Achillea millefolium 0 0 0 <0.1

Aster alpigenus 1 0.1 0.2 <0.1

Calamagrostis canadensis 1 0.3 0.8 <0.1

Danthonia intermedia 2 0.1 0.2 <0.1

Hypericum formosum 1 <0.1 <0.1 <0.1

Oryzopsis exigua 1 0.1 0.4 <0.1

Polemonium pulcherrimum 1 0.1 0.4 <0.1

Spiraea betulifolia 1 0.1 0.3 <0.1

Penstemon globosus 1 0.7 2.5 <0.1

Phleum alpinum 3 0.4 0.4 <0.1

Sitanion hystrix 0 0 0 <0.1

a

 Species that were unintentionally and non-systematically transplanted.
20 USDA Forest Service RMRS-GTR-185. 2007

cover has increased and many species have been reestablished on the sites. However, total vegetation cover 

remained diminished after 10 years (fig. 26). Even more 

problematic is the minimal cover provided by shrubs, 

particularly Vaccinium scoparium and Phyllodoce empetriformis. Neither of these species responded well to 

the treatments we applied. Transplanting helped, but 

more than one-half of the shrub transplants died and the 

soil amendments did not result in increased growth.

Treatment Effects

Most of the treatments contributed to recovery. Little 

recovery would have occurred if campsites had not been 

effectively closed to all human entry. Conversely, closure alone was not very effective. Mean cover on plots 

that were closed to use but not scarified was 0.5 percent 

after 10 years. Scarification was effective in promoting 

recovery, but as with closure, it is not sufficient. Mean 

cover on plots that were only scarified was 2.5 percent 

after 10 years.

Mulch blankets—Surprisingly, the mulch blankets 

had no appreciable effect, despite the fact that they are 

frequently employed and recommended (Urbanska and 

Chambers 2002) and have been shown to be effective 

in research conducted in other high-elevation ecosystem types (Petersen and others 2004). Fattorini (2001) 

reported that mulch blankets on ski runs in the Alps had 

Table 19. Species that volunteered—the number of camps and percent of plots where they established, 

as well as mean percent cover, in 2005.

Species Number of camps Plot frequency Mean cover

Carex rossii 6 96 3.0

Juncus parryi 6 53 0.5

Muhlenbergia filiformis 5 42 0.3

Vaccinium scopariuma 5 28 0.2

Pinus contorta 6 65 0.1

Picea engelmannii 5 60 0.1

Antennaria alpina 3 21 0.1

Polygonum kellogii 2 17 0.1

Carex phaeocephala 3 13 0.1

Carex microptera 1 3 0.1

Abies lasiocarpa 3 26 <0.1

Lewisia pygmaea 3 15 <0.1

Erigeron peregrinusa 3 6 <0.1

Gayophytum ramosissimum 2 14 <0.1

Polemonium pulcherrimum 2 10 <0.1

Sibbaldia procumbens 2 10 <0.1

Hieracium gracilea 2 6 <0.1

Luzula hitchcockiia 2 3 <0.1

Spraguea umbellata 1 10 <0.1

Calamagrostis canadensisa 1 6 <0.1

Linanthastrum nuttallii 1 3 <0.1

Penstemon fruticosus 1 3 <0.1

Veronica cusickiia 1 3 <0.1

Epilobium angustifolium 1 1 <0.1

Festuca viridulaa 1 1 <0.1

Hypericum formosuma 1 1 <0.1

Juncus mertensianus 1 1 <0.1

Ligusticum tenuifolium 1 1 <0.1

Oryzopsis exigua 1 1 <0.1

Penstemon globosus 1 1 <0.1

Phleum alpinum 1 1 <0.1

Polygonum phytolaccaefolium 1 1 <0.1

Spiraea betulifoliaa 1 1 <0.1

Aster alpigenus 2 4 0

Antennaria lanata 2 3 0

Sagina saginoides 1 3 0

Castilleja chrysanthaa 1 1 0

Cerastium vulgatum 1 1 0

Luzula campestris 1 1 0

Rorippa islandica 1 1 0

Sitanion hystrix 1 1 0

a

 Plants of these species may have been transplants or sprouts rather than volunteers.
USDA Forest Service RMRS-GTR-185. 2007 21

no effect on transplant survival. Their primary effect 

was a reduction in flowering. In our study, lack of effect may reflect the unusually good growing conditions 

that existed for the first two summers. Survival of both 

transplants and seedlings was extremely high in these 

seasons. By the third summer, when hotter and drier 

conditions prevailed, the mats had already disintegrated. 

While they were not worthwhile under our working conditions, we are reluctant to conclude that they would not 

be worthwhile under other circumstances. More research 

on mulch mats is needed. They can also have other beneficial effects, such as deterring recreational use of the 

site and reducing erosion on steep slopes.

Soil amendments—The organics and compost soil 

amendment was clearly effective in accelerating recovery. It was effective in raising levels of organic carbon 

and potentially mineralizable nitrogen, and increasing 

microbial activity in soils where these characteristics 

had been adversely affected by decades of disturbance 

and lack of organic inputs (fig. 7). These changes, perhaps along with other unmeasured changes (such as bulk 

density, porosity, and water holding capacity), likely explain the higher levels of vegetation cover on plots given 

this amendment. Numerous other studies, conducted in 

diverse ecosystems (such as Caravaca and others 2002), 

have reported positive effects of compost on restoration 

success.

This amendment was more effective in promoting 

the cover of seedlings than of transplants. Our careful monitoring of seedling establishment and mortality, 

along with our root and shoot biomass 

measurements, show that while this 

amendment had no effect on germination and establishment rates, it benefited 

seedlings by making them less prone 

to mortality after they had become established. For the first 2 years, at least, 

seedlings growing in soil amended with 

organics and compost had much larger 

shoots and root systems than seedlings 

growing in soil that did not receive this 

amendment (fig. 27). This suggests that 

much of the beneficial effect of this 

treatment came from the nutritional input of the compost.

The effect of the additional nutrients 

in the compost on transplants was visually obvious, particularly 2 to 5 years 

after transplanting. As reported in Cole 

and Spildie (2006), transplants growing in plots amended with organics 

and compost were unusually large. By 

2005, presumably because the additional nutrients supplied by the compost had been depleted, transplants on 

composted plots were no longer visually larger. Perhaps 

the most important long-term beneficial effect of this 

treatment was increased survivorship for Vaccinium scoparium transplants. Reestablishment of V. scoparium is 

both the most important and the most challenging aspect 

of restoring these sites. Any treatment that has a positive 

effect is important.

Results regarding the effectiveness of the amendment of soils with local organic matter, peat moss, and 

Figure 26. After 10 years of recovery, cover has increased, but is still sparse.

Figure 27. Unusually large Phleum alpinum seedlings on plots 

amended with compost, 2 years after treatment.
22 USDA Forest Service RMRS-GTR-185. 2007

native soil inoculum (but no compost) are less conclusive. 

This amendment was an attempt to reintroduce native 

soil biota and ameliorate some of the adverse physical 

properties of campsite soils, by increasing water holding 

capacity and reducing susceptibility to compaction but 

to not ameliorate the reduced levels of plant-available 

nitrogen on campsite soils. For virtually every measure 

of soil characteristics and vegetation response, values 

for plots with this amendment were intermediate between those for plots that were not amended and plots 

that were amended with organics and compost. In 2005, 

total cover on organics plots was 1.3 times the cover on 

unamended plots. Seedling cover was 1.6 times as high, 

while transplant cover was not different. These results 

are in line with our expectations. However, for most of 

our measures of response, differences between this treatment and the other two treatments were not statistically 

significant at an alpha level of 0.05. For effects on total 

cover and seedling cover, p-values were 0.16 and 0.13, 

respectively.

Therefore, we cannot conclude with a high degree 

of confidence that addition of local organic matter was 

beneficial. Conversely, the power of statistical tests was 

low, given our small sample size and substantial variation among the six campsites. Consequently, we also 

cannot conclude with a high degree of confidence that 

the increased cover observed on plots that received the 

organics amendment is not the result of the treatment. 

The beneficial effects we can be most confident about 

(differences were statistically significant at an alpha of 

0.05) are increased organic carbon and total nitrogen in 

the soil, survival of Vaccinium scoparium transplants, 

growth of Carex rossii transplants and density of Carex 

rossii seedlings.

Seeding and transplanting—Both seeding and 

transplanting were effective. On plots that were both 

seeded and transplanted, mean cover of volunteers after 10 years was 3.9 percent. Seeding added another 

6.3 percent, while transplanting added another 12 percent for a total of 20.2 percent cover on transplanted and 

seeded plots. On plots that were not seeded and transplanted, mean cover after 10 years (all volunteers) was 

5.8 percent. Transplants had little effect, either positive 

or negative, on seedlings when planted at the densities 

at which we planted them. The fact that seedling density 

was lower within transplant canopies suggests that transplanting might inhibit seedling establishment if planted 

more densely.

Treatments and recovery rates—Table 20 provides 

a means for comparing the effectiveness of different 

treatments in various combinations. It assumes a linear extension into the future of the recovery rates that 

occurred over the past 10 years, reporting the number 

of years it would take to restore the target condition of 

50 percent vegetation cover. Although future recovery 

rates are unlikely to be equivalent to rates during the 

first 10 years, the table emphasizes the lengthy recovery periods required regardless of treatment, as well as 

the need to apply intensive treatments if we intend to restore these sites within our lifetime. By working the soil, 

recovery time can be reduced to about 50 years, while 

with the addition of planting it can be reduced to about 

20 years (table 20). Of the planting treatments, seeding 

is more effective than transplanting in reducing recovery time where soils are amended. In the absence of soil 

amendments (table 21), transplanting is more effective 

than seeding in reducing recovery time; however, in the 

absence of soil amendments, recovery time exceeds 30 

years even with both seeding and transplanting.

Our evaluation of treatment effectiveness changes, 

however, if our criterion for success is the reestablishment of native species composition. Treatments were 

much more effective in restoring species richness than in 

restoring cover. The mean number of species on campsites was 13, close to the 15 species that is typical of 

undisturbed sites. Seeding and transplanting were by far 

the most effective treatment. Scarification had a small 

but statistically significant positive effect, but mulching 

and amending soils had no effect.

Table 21. Estimated time (in years) to recovery of 50 percent 

vegetation cover, without soil amendments, assuming linear 

extrapolation of the past 10 years.

Years to recovery

Closure + scarification 200

+ seeding 84

+ transplanting 34

Transplanting, but not seeding 4

Table 20. Estimated time (in years) to recovery of 50 percent 

vegetation cover, assuming linear extrapolation of the past 

10 years.

Years to recovery

Closure 1000

+ scarification 200

+ mulch mat 200

+ organics 100

+ compost 56

+ seeding 31

+ transplanting 19

Transplanting, but not seedinga 36

a

 On plots with organics and compost amendments.
USDA Forest Service RMRS-GTR-185. 2007 23

Treatments were less effective in restoring the native species composition of these sites than in restoring 

cover. After 10 years, shrub cover was only 11 percent, 

compared to 57 percent on reference sites. The most 

abundant species on reference sites, Vaccinium scoparium and Phyllodoce empetriformis, had mean cover on 

campsites of only 2.5 percent and 0.4 percent, respectively. Of the treatments, transplanting was by far the 

most effective for establishing these species. The only 

P. empetriformis plants on the campsites after 10 years 

were transplants. We observed a few small V. scoparium 

plants that were not transplants (probably stem sprouts 

rather than seedlings), but virtually all V. scoparium

cover is provided by transplants. In combination with 

transplanting, the soil amendments may also be effective because more V. scoparium transplants survived on 

amended soils.

Further Research

It is important to remember that these general categories of treatment (such as planting and soil amendment) 

refer to very specific treatments. If we had used different planting treatments (different species, larger or 

smaller transplants, more transplants, more or less seed) 

results would have been at least quantitatively different. 

Further experimentation with planting techniques would 

be worthwhile. Particularly useful would be experimentation with planting of established plants grown from 

seed in nurseries. Theoretically it should be possible 

to reduce recovery time greatly by planting transplants 

at densities several times greater than the five to seven transplant plugs per square meter used in this study. 

Experimentation with dense plantings of Vaccinium scoparium and Phyllodoce empetriformis, both of which 

survived no more than half the time, would be particularly useful.

Opportunities for further experimentation with soil 

amendments are even more diverse. As noted earlier, 

amendments can serve to ameliorate the adverse effects of camping both on soil physical properties and 

on nutritional properties. Applying locally-derived organic matter of differing types and quantities could be 

tried. Highly-decomposed organics might be particularly effective in increasing water-holding capacity and 

reducing the tendency for scarified soils to become compacted by rainfall and snow loading. Materials such 

as long pine needles, twigs and small branches might 

be effective in promoting water infiltration into soils. 

Other sources of long-lasting supplemental nutrition, 

released in small quantities, could be employed. For example, Paschke and others (2000) report that the organic 

fertilizer Biosol® was effective in promoting plant 

growth on roadcuts. The depth of scarification and depth 

to which amendments are mixed could also be varied. 

Finally, it would be worthwhile to replicate the treatments applied in this study, in different places, to assess 

if the results are site-specific.

Treatment Needs of Individual Species

Individual species varied greatly in how easy they 

were to restore to reference conditions. This study provided substantial insight into the treatments necessary to 

effectively restore the most abundant species.

Graminoids—Juncus parryi and Carex rossii, the 

most abundant graminoids, transplanted well. Every 

transplant of these species survived and grew substantially (Cole and Spildie 2006). J. parryi also established 

well when seeded and a modest number of seedlings 

volunteered. These seedlings survived in sufficient 

quantities to approximate target conditions after 10 

years. Although C. rossii was not seeded, it volunteered 

profusely, exceeding target conditions after 10 years. 

Results suggest that transplanting may be unnecessary 

for these species and even seeding may be unnecessary 

for C. rossii. However, C. rossii established and survived much more frequently on plots with either of the 

soil amendments, suggesting that amendment with organics is important if this species is left to reestablish on 

its own (fig. 28).

Forbs—The most abundant forbs planted were 

Antennaria lanata, Antennaria alpina, and Sibbaldia 

procumbens. Both A. lanata and S. procumbens became 

well-established only where they were planted. Both 

Figure 28. Abundant Carex rossii seedlings that volunteered 

on plots amended with organic matter.
24 USDA Forest Service RMRS-GTR-185. 2007

species established well from transplants and seed, although A. lanata established particularly well from seed. 

Transplanting was more effective for S. procumbens. A. 

alpina transplants often did not survive or grow well. 

However, this species established prolifically from seed. 

In fact, it volunteered often enough to suggest that seeding may be unnecessary. For each of these species, cover 

was greater on amended plots than on plots that were 

not amended. Where they were planted, S. procumbens 

reached its target coverage even on unamended plots, A. 

alpina reached its target only on amended plots (either 

amendment), and A. lanata did not reach its target on 

any treatment. Veronica cusickii, the most abundant forb 

not intentionally planted, established only in the plugs 

we transplanted on the campsites.

Trees—Most of the small trees that we transplanted survived and grew well, particularly Pinus contorta 

(fig. 29). Seedlings of P. contorta, Abies lasiocarpa, and 

Picea engelmannii volunteered in substantial numbers 

but growth rates were so low that cover after 10 years 

was negligible. Soil amendments had no effect on either 

transplants or tree seedlings.

Shrubs—The most difficult species to establish were 

the shrubs. It is quite likely that none of the shrubs established from seed. We found six new shoots of Vaccinium 

scoparium on plots that had not been transplanted, but 

it is likely that these are root sprouts rather than seedlings. Therefore, transplanting is critical to restoration of 

shrub species. However, transplant survivorship was 50 

percent or less for all three shrub species, V. scoparium, 

Phyllodoce empetriformis, and Spiraea betulifolia. Soil 

amendments increased survivorship for V. scoparium, 

but not the other shrubs. Amendments had no effect on 

shrub transplant growth or cover. Clearly, identification 

of treatments that can increase survivorship and growth 

of V. scoparium and P. empetriformis transplants is the 

most important research need. Transplanting at much 

greater densities than we used might also prove successful.

Uncommon species—None of the uncommon species planted would have established often on these 

campsites without planting. Of these, Penstemon globosus was by far the most successful. It established 

profusely when seeded. It survived at higher densities 

and grew more rapidly on plots that had been amended, although it survived at adequate densities on non 

amended plots. We seeded Phleum alpinum on three of 

the campsites. Large numbers of seedlings germinated 

and established, but most of them have eventually died. 

Still, in 2005, P. alpinum cover exceeded its target cover. Another grass, Danthonia intermedia, responded in a 

similar manner. Large numbers of seedlings established, 

but after 10 years, few were alive. Small quantities of 

the Aster alpigenus that established from seed were still 

alive in 2005, but none of the few Sitanion hystrix seedlings survived. By transplanting at covers that exceeded 

their target covers, Aster alpigenus, Calamagrostis canadensis, Danthonia intermedia, Luzula hitchcockii, 

Oryzopsis exigua, and Polemonium pulcherrimum all 

exceeded target covers after 10 years, despite low survivorship for L. hitchcockii and poor growth for A. 

alpigenus. Hypericum formosum transplants did very 

poor, but a few survived after 10 years. None of the 

transplants of Achillea millefolium survived. This was 

surprising, since A. millefolium is often a weedy plant.

Management Implications

A Prescription for Campsite Restoration

Our results suggest the following prescription should 

provide vegetative recovery of campsites in this vegetation type on a time scale of decades rather than a century 

or longer.

Effectively close the campsite to all use. Rope off the 

perimeter and post signs that instruct people to stay 

off the site and explain why.

Scarify soils to a depth of at least 15 cm. Break up all 

clods to produce a crumb texture.

Amend soils with at least a 2.5 cm layer of locally 

collected, well decomposed organic matter. Add an 

equivalent amount of compost. Alternatively, mix in a 

smaller amount of bioorganic fertilizer. For example, a 

1.

2.

3.

Figure 29. Percent cover of the Pinus contorta transplant on 

this plot increased 15-fold in 10 years.
USDA Forest Service RMRS-GTR-185. 2007 25

bioorganic fertilizer with 6 or 7 percent N could be 

applied at a rate of about 18 kg per 100 m2.

Transplant Vaccinium scoparium and Phyllodoce empetriformis (if appropriate to the site) at densities at 

least as high as their densities on undisturbed sites. 

Consider growing these shrubs in nurseries, from seed 

collected close to the site. It also seems highly beneficial to transplant some small trees. If only a few sites 

are being restored, it may not be necessary to grow 

trees in nurseries. Juncus parryi is the next transplant 

priority. This transplanting will probably be sufficient 

to inoculate the soil with native biota.

Collect seed from a wide variety of species growing 

in the vicinity, preferably a year before restoration. 

Match the species sown to site conditions. Some species, such as Carex rossii and Juncus parryi, are appropriate on virtually all sites. Others, such as Penstemon 

globosus, may be important only on certain sites. 

Worthwhile species to seed include: Antennaria alpina, Antennaria lanata, Aster alpigenus, Erigeron 

peregrinus, Sibbaldia procumbens, and Veronica cusickii. It may be unnecessary to seed Carex rossii or 

Juncus parryi, if J. parryi is transplanted.

The benefits of using a mulch blanket are unclear. It is 

not harmful, however, and can have benefits such as 

keeping people off the site.

If possible, water plants during long, dry spells. This 

is most important in the first few growing seasons. 

However, we had transplants that had been growing 

well, die 4 years or more after transplanting.

At a minimum, inspect the closures at the start of every year to verify that ropes and signs are still up.

Restoration and Visitor Management

Restoration treatments dramatically accelerate recovery rates on closed campsites in subalpine forests. 

However, complete recovery will require many decades. 

Avoiding recreation impacts in the first place is more 

effective than restoring conditions after impacts occur. 

To promote the general principle of employing the minimally restrictive effective management technique, it 

has sometimes been asserted that wilderness managers 

should only restrict recreation (use direct management 

techniques) after unrestrictive (indirect) techniques are 

proven ineffective. When the outcome of ineffectiveness 

is biophysical impact, this assertion is inappropriate, 

particularly in ecosystems such as the subalpine forests we studed. In similar forests, Cole and Monz (2003) 

showed that one night of camping typically eliminated about one-half of the understory vegetation. Since 

4.

5.

6.

7.

8.

impact occurs so rapidly and it takes decades for impacted vegetation to recover, wilderness managers need 

to proactively employ management techniques that will 

ensure that impacts do not exceed acceptable levels. 

They should not wait to prove that indirect techniques 

are ineffective.

As demonstrated in this study, restoration is costly in 

terms of effort, and particularly, time. In a wilderness 

such as the Eagle Cap, there may be hundreds of campsites that might be considered in need of restoration. It is 

not clear that we can afford to restore all these sites. To 

attempt substantial restoration, planning, training, and 

experimentation are critically important. It is not costeffective to ask untrained wilderness rangers to do some 

restoration when they have time.

It is important to carefully decide which campsites 

to restore. At the lakes in the Eagle Cap Wilderness, it 

might be worthwhile to develop “hundred-year restoration plans” for each lake. One-fifth of the lakeshore 

could be roped off. Desired social trails, picnic sites, 

viewpoints, and so on, could be mapped. Impacted 

places not part of this infrastructure could be restored. 

With highly effective restoration treatments, these areas might be reopened to use in about 20 years. At 

that point, restoration of the next one-fifth of the lake 

could begin. With this approach, restoration of the entire lakeshore might be possible in 100 years. Without 

such planning, restoration will take much longer—if it 

occurs at all.

Because restoration is so costly, experimentation and 

monitoring are critical. It is important to identify the 

most effective means of restoring sites before large-scale 

restoration is attempted. The treatments employed in our 

study were not sufficient to restore the dominant shrubs 

in the understory. The identification of treatments that 

maximize survival and growth of these species remains 

a very high priority, particularly given the millions of 

hectares and thousands of campsites in western wilderness that are within this ecosystem type.

Finally, it is also critically important to ensure that restored campsites are never used again. The key here is to 

make it clear where people should and should not camp, 

and then to enforce closures. Both site manipulation 

and visitor management play a role in keeping people 

off recovering sites. As noted above, much can be accomplished by carefully planning an infrastructure of 

campsites and travel routes that meet the needs of visitors. At a more localized scale, large rocks can be buried 

in the middle of tent pads, their exposed parts making 

the pad unusable. Ultimately, however, it may be necessary to require visitors to use established or designated 

campsites and to enforce such regulations.
26 USDA Forest Service RMRS-GTR-185. 2007

References

Caravaca, F.; Barea, J.M.; Figueroa, D.; Roldán, A. 2002. 

Assessing the effectiveness of mycorrhizal inoculation and 

soil compost addition for enhancing reafforestation with 

Olea europaea subsp. sylvestris through changes in soil 

biological and physical parameters. Applied Soil Ecology 

20: 107-118.

Cole, David N. In press. Seedling establishment and survival 

on restored campsites in subalpine forest. Restoration 

Ecology.

Cole, David N.; Fichtler, Richard K. 1983. Campsite 

impact in three western wilderness areas. Environmental 

Management 7: 275-288.

Cole, David N.; Monz, Christopher A. 2003. Impacts of 

camping on vegetation: response and recovery following 

acute and chronic disturbance. Environmental Management 

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Cole, David N.; Spildie, David R. 2006. Restoration of plant 

cover in subalpine forests disturbed by camping: success of 

transplanting. Natural Areas Journal 26: 168-178.

Fattorini, Marzio 2001. Establishment of transplants on 

machine-graded ski runs above timberline in the Swiss 

Alps. Restoration Ecology 9: 119-126.

Hitchcock, C. Leo; Cronquist, Arthur. 1973. Flora of the 

Pacific Northwest. Seattle, WA: University of Washington 

Press. 730 p.

Lester, William J. 1990. Revegetation efforts at North 

Cascades National Park Service Complex. In: Hughes, 

H. Glenn; Bonnicksen, Thomas M., eds. Restoration ’89: 

the new management challenge. Proceedings, first annual 

meeting of the Society for Ecological Restoration. 1989 

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Moritsch, Barbara J.; Muir, Patricia S. 1993. Subalpine 

revegetation in Yosemite National Park, California: 

changes in vegetation after 3 years. Natural Areas Journal 

13: 155-163.

Paschke, Mark W.; DeLeo, Claire; Redente, Edward F. 2000. 

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Park, U.S.A. Restoration Ecology 8: 276-282.

Petersen, S.L.; Roundy, B.A.; Bryant, R.M. 2004. Revegetation 

methods for high-elevation roadsides at Bryce Canyon 

National Park, Utah. Restoration Ecology 12: 248-257.

Urbanska, Krystyna M.; Chambers, Jeanne C. 2002. Highelevation ecosystems. In: Perrow, M.R; Davy, A.J., eds. 

Handbook of Ecological Restoration, Volume 2: Restoration 

in Practice. Cambridge, UK: Cambridge University Press: 

376-400.

Zabinski, Catherine A.; DeLuca, Thomas H.; Cole, David 

N.; Moynahan, October S. 2002. Restoration of highly 

impacted subalpine campsites in the Eagle Cap Wilderness, 

Oregon. Restoration Ecology 10: 275-281.
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