2013-07-09_PERMIT FILE - C1981010A (20)

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• 2.3 VEGETATION The most prevalent vegetation type throughout most of the Williams Fork Moun- tains is mountain shrub. In northwestern Colorado, this type typically inter- faces with stands of big sagebrush associated with various species of grass at its lower elevation limits and with aspen types at higher elevations (refer to Map M16). The proposed mine plan area supports heavy stands of the mountain shrub type on the east half (Sections 5 and 6 of Township SN, Range 90W; Sections 29, 30, 31 and 32 of Township 6N, Range 90W; Sections 1, 2, and 3 of Township SN, Range 91W; and Sections 35 and 36 of Township 6N, Range 91W) . From the mid-point of the proposed mine plan area westward the mountain shrub type begins to thin, espe- cially at the lower elevations, until it is replaced by a big sagebrush-grass type. On this west half of the proposed mine plan area (Section 4 of Township SN, Range • 91W; Section 34 of Township 6N, Range 91W and Section 25 of Township 6N, Range 91W and continuing westward) the heavy mountain shrub community gives way to scattered islands of serviceberry and chokecherry growing in a predominately sagebrush covered landscape. Here the serviceberry and chokecherry are confined within small valley-like eroded drainages and in the moister microclimates under the north Lip of ridges and hilltops. The mountain shrub type of the proposed mine plan area is characterized at higher elevations (7,200 feet +) by Gambel's oak (Quercus gambelii), serviceberry (Amelanchier alnifolia), and chokecherry (Prunus virginiana). Snowberry (Symphoricarpos oreophilus) is also found growing in the unders[ory throughout the type. In scattered openings of dense oak and serviceberry-chokecherry cover, occasional big sagebrush (Artemisia tridentata), and snowberry are found mixed with minor amounts of rubber rabbitbrush (Chrysothamnus nauseosus) and antelope bitterbrush (Purshia tridentata). On west facing slopes of lower elevations, oak is dominant to serviceberry and chokecherry. In the more mature shrub communi- ties within the proposed permit area, oak commonly attain heights of 10-12 feet. • 2-58 1l~VISED FEB 13 '87