2006-06-02_PERMIT FILE - C1980007 (5)

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West Elk Mine Seven herbaceous species (four graminoid, three forb species) were sampled in the 50-meter transect, providing 57 percent average cover. Height in the herbaceous stratum ranged from 5 to 30 cm (2 to 12 in.). Kentucky bluegrass was the most important graminoid species, providing 34 percent cover, and occurring in 70 percent of the azea sampled. Littleflower collinsia was the most important forb species, providing 1.6 percent cover. Litter cover was sparse. Jun' er The juniper vegetation community within the 1976 study area is distinguished by the presence of mature juniper trees (Juniperus osteosperma and Juniperus scopulorum), ranging in height from 3-5 m (10-15 ft.). Rocky Mountain juniper (Juniperus scopulorum) appeazs to be more common than Utah juniper (Juniperus osteosperma) in the study area. Understory shrub species in this community frequently consist of big sagebrush and fourwing saltbrush (Atriplex canescens), growing to a height of 1 m (3 ft.). The juniper community occurs primarily on steep, south and east-facing slopes on shale and sandstone outcrops and is found along south-facing slopes above the North Fork of the Gunnison River. It is found between 1,800 and 2,400 m (6,000-8,000 ft.) in elevation in the study area. Other occurrences of this community are on west- and south-facing slopes along the East Fork of the Minnesota Creek. Abrupt changes in vegetation composition are particulazly evident on steep slopes mapped north of the North Fork of the Gunnison River. The tree stratum consisted entirely of Utah juniper and provided 33 percent cover. The shrub stratum sampled consisted of two species, providing six percent cover, and averaging 0.5 m (1.5 ft) in height. Snowberry, the most important species, provided all the recorded cover. Big sagebrush was also sampled. Although not sampled, greasewood (Sarcobatus vermiculatus) and rubber rabbitbrush were observed growing on slightly deeper soils on the flanks of small gullies. Seven herbaceous species (four graminoid, three forb species) were sampled along the 50-meter transect, providing only 12 percent cover. Herbaceous stratum height ranged between 5 and 20 cm (2-8 in.). Japanese brome (Bromus japonicus) was the most important graminoid species, providing three percent cover, and occurred in 40 percent of the sampled azeas. Helianthella (Helianthella quinguinerris) and longleaf phlox (Phlox longifolia) were the most important forb species. The only litter observed was that found under trees. Riparian The Riparian vegetation community within the 1976 study azea is distinguished by its occurrence along the drainages of permanent and ephemeral streams in the study area. Specifically, riparian areas occur along the North Fork of the Gunnison River, and along permanent and intermittent stream channels in the Minnesota Creek and Deep Creek drainages. Vegetation composition is variable, depending on elevation, aspect, floodplain morphology, and hydrology. Riparian vegetation is sustained by the soil and hydrological characteristics supplied by the associated river or stream. At elevations below 1,950 m (6,500 ft.) this type is characterized by the frequent presence of narrowleaf cottonwood and box-elder (Ater negundo}trees 9-12 m (30 to 40 ft.) tall. At higher elevations, species typical of the oakbrush community (Gambel oak and serviceberry) aze frequent in riparian communities. Hawthorn (Crataegus sp.) and willows (Salix sp.) aze especially common along most drainages. Colorado blue spruce reaches its lowest point of occurrence in the study azea in the riparian community along 2.04-141 Revised November 1004 PRt 0