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mountain loam range site is similar to the sagebrush type. The deteriorated range condition is reflected in a <br />higher density of shrubs at the expense of the herbaceous component. According to SCS range site • <br />descriptions and analysis of regional baseline vegetation data, shrub densities may be two to four times <br />higher than the allowable amounts for optimum range condition. Aspen stands have also been affected by <br />livestock grazing, particularly sheep grazing. The aspen stands in the permit area are characterized by a <br />poor understory vegetation and a distinct lads of regeneration. Existing stands are dominated by mature and <br />decadent trees. These observations are consistent with those in other areas of the west (DeByle and <br />Winokur, 1985). <br />While diminished range condition pn be attributed to livestock grazing, it is further compounded by the <br />ecological characteristics of the woody plant communities and the livestock and big game utilization patterns <br />occurring in these communities. The woody component in these communities readity increases when the <br />herbaceous component is reduced in vigor or eliminated. The mountain brush type represents well <br />established Banal communities that readity exploit opportunities for expansion in the presence of <br />perturbations to herbaceous vegetation such as overgrazing. Similarly, snowbeny and sagebrush will <br />occupy niches formerly occupied by herbaceous spades. Tisdale and Hiranaka (1981), in an extensive <br />review of the literature on the sagebrush grassland region, found overall use of sagebrush by wildlife antl <br />livestodk combined was generally light This resuRed in minimal impact to sagebrush, especialty in relation <br />to the associated herbaceous component. They also found sagebnrsh stands have a strong competitive <br />edge once herbaceous competition is reduced. <br />Cattle and sheep do not graze in the permit area during the winter months, thus eliminating any winter • <br />browsing of woody spades by livestock. Livestodk grazing usually begins in mid to late June. During the <br />summer months, both cattle and sheep center their foraging preferences on the more nutritious and <br />palatable herbaceous species. While some browsing of the woody spades by livestock does occur during <br />the summer, it is generally limited because of the availability of more palatable herbaceous spades. This <br />grazing selection has favored The woody component in these native stands. <br />The highest use of browse by big game is expected to occur during the winter months when browse spades <br />are dormant or in the spring before signficeM herbaceous production. During the summer months, use of <br />browse will drop sorneWitrat and big game will increase use of the more nutritious and palatable herbaceous <br />spades. This will again favor the woody componerd. <br />The use patterns of browse by big game, coupled with the ability of the woody spaces to increase under <br />livestock grazing, has resuRed in higher woody plant densties. Based on personal observations, <br />discussions wigr SCS range conservationists Tram the Craig and Steamboat Springs offices. the State SCS <br />range conservationist in Denver, antl plats ecologists Tram area mines, the somewhat degraded plant <br />community charaderis6cs for the maed brush and sagebnrsh types found on the Seneca II Mine are <br />common in northwestern Colorado. <br />Wildlife Habitat and Ulil¢ation of Native Ranoeland. The Seneca II permit area is located in a region that is <br />utilized by a variety of wikflife species. The three primary undisturbed vegetation types present (sagebnush, <br />mixed brush, aspen) provide food and cover habRat for many of the wildlife spades year-round. Of particular <br />TR37 732 Revised 04/05 <br />