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site and mountain loam range site, estimated range cond~i lion for the mixed brush and sagebrush types occurring in the area is only fair. The brushy Loem range site equates to the mountain brush vegetation type, while the mountain loam range site is similar to the sagebrush type. The deteriorated range condition is rtrflected in a higher density o~f shrubs at the expense of the herbaceous component. .4c cording to SCS range site descriptions and analysis of regional baseline vegetation date, shrub densities rosy be two to four times higher than the allowable amounts for optimum range condition. Aspen stands have also been affected by livestock grazing, particularly sheep grazing. The aspen stands in the permit area are characterized by a poor undo r::t ory vegetation and a distinct lack of regeneration. Existing stands are dominated by a~a iure and decadent trees. These observations ere consistent with [hose in other areas of the west (DeByle and Winokur, 1985). while diminished range condition can be attributed to livestock grazing, it is further compounded by the ecological characteristics of [he woody plan[ communities and the livestock and big game utilization patterns occurring in these communities. The woody component in these communities readily increases when the herbaceous component is reduced in vigor or eliminated. The mountain brush type represents well established clonal communities that are readily capable of exploiting opportunities for expansion in the presence of perturbations to herbaceous vegetation such as overgrazing. Similarly, snowberry and sagebrush will occupy niches formerly occupied by herbaceous species. Tisdale and Hironaka (1981), in an extensive review of the literature on the sagebrush grassland region, found overall use of sagebrush by wildlife and livestock combined was generally light. This resulted in minimal impact to sagebrush, especially in relation to the associated herbaceous component. They also found sagebrush stands have a strong competitive edge once herbaceous competition is reduced. Cattle and sheep do not graze in the permit area during the winter months, thus eliminating any winter browsing of woody species by livestock. Livestock grazing begins in late May or early June. During the summer months, both cattle and sheep center their foraging preferences on the more nutritious and palatable herbaceous species. While some browsing of the woody species by livestock does occur during the summer, it is generally limited because of the availability of more palatable heerbaceous species. This grazing selection has favored the woody component in these native strands. The highest use of browse by big game is expected to occur during the winter months when • 13-2 Revised 01/75/93