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ingly, percetage of bare ground was low, ranging from 1-9$. Plants which were important in the biomass plots were generally also important in the herbaceous cover estimates. Species composition percentages were similar between the mine and reference areas. Sample adequacy require- ments were met in both areas. 3.3.3 Woody Plant Density Results are presented here separately for shrub and tree components of woody vegetation, since these components were counted separately in different-sized quadrats. Table A.5 contains this data for both mine and reference areas. Up to five shrub/seedling species occurred in the 2 x 25 m quadrats, snowberry (Symphoricarpos oreophilus) was the most abundant. Each of the remaining four species, serviceberry (Amelanchier alnifolia), aspen seedlings ( 2m tal)), chokecherry and gooseberry (Ribes inerme), were of comparable abundance. Shrub density ranged from 78-135 plants per quadrat. The mean density of shrubs and seedlings per quadrat on the mine area was 117.8 ± 17.3 versus 94.8 ± 18.2 on the reference area. Both areas were sampled sufficiently to meet the statistical requirements, four samples were taken on the mine area and six were taken in the ref- erence area. Tree density (including shrubs 2m tall) was also adequately sampled on both sites. Aspen was the predominant tree, and measurements showed a higher density on the mine area (57.8 t 7.1 vs. 37.3 ! 5.5 trees/quadrat). The mine azea also had more dead trees than the reference area, though these weren't counted. 3.4 Sagebrush Vegetation Type The sagebrush vegetation type was the most extensive within the mine permit area. Sagebrush nearly always occurred with snowberry and this community type was found on virtually all slope, aspect and elevational situations. Unlike the aspen type, boundaries of this community were • indefinite, intergrading gradually with. .other shrub-dominated types.