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

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West Elk Mine • Characteristic shrub species in the understory of the Douglas fir community aze servicebeny and snowberry, ranging in height from 1-5 m (3-15 ft.). The Douglas fir community is generally located in azeas of steep, north-facing slopes in the 1976 study area. These areas occur primarily above the town of Somerset, along drainages leading into Sylvester Gulch, on the flanks of the West Flatiron, and above the North Fork of the Gunnison River on the eastern portion of the Box Canyon lease tract. Douglas fir stands also occur along the drainage of the East Fork of Minnesota Creek and below Beaver Reservoir in the southern portion of the study area. These stands may also contain scattered individuals of Colorado blue spruce (Picea pungens). Most stands occurring in the study azea range from 2,250-2,400 m (7,500-8,000 ft.) in elevation. The Douglas fir community intergrades with the oakbrush community along transitions between cool north-facing slopes and warm east- and south-facing slopes. The representative location of the Douglas fir community sampled is located on soil mapping unit number 6. The tree stratum within this type consisted almost entirely of Douglas fir and provided a total of 71 percent cover. A single individual of nanowleaf cottonwood (Populus angustifolia) was the only other tree species within the sample azea. The shrub stratum within the Douglas fir community consisted of 10 species and provided 62 percent cover. Shrub species were much shorter than those observed in the Aspen community, and did not form two distinct layers. Average height for neazly all shrub species was 0.5 m (1.6 ft.). The dominant species was serviceberry providing 23 percent cover. Eleven herbaceous species (one graminoid and 10 forbs) were sampled along the 50-meter intercept line, providing 45 percent average cover. The majority of the cover was provided by scattered, lazge plants with large crown areas. Height of the herbaceous stratum ranged between 10 and 30 cm (4-12 in.). Elk sedge was the only graminoid species sampled, providing one percent average cover, and occurring in 20 percent of the sampled azea. The most important forb species was arnica (Arnica cordifolia), which provided 36 percent average cover, and occurred in 80 percent of the quadrants sampled. Litter accumulation, consisting primarily of Douglas fir needles, was extensive throughout this stand, reducing the potential for erosion on the steep slopes. Xeric Mountain Shrub The xeric mountain shrub community is distinguished by scattered individuals of several shrub species. These include serviceberry, Gambel oak, and secondarily mountain mahogany (Cercocarpus montanus), cliff fendlerbush (Fendlera rupicola) and bitterbrnsh (Purshia tridentata). Skunkbush sumac (Rhus trilobata) may form a locally important component of this community. The xeric mountain shrub community occurs primarily on steep, south- and west-facing slopes and frequently on sandstone and shale outcrops in an elevation range of 1,800-2,400 m (6,000-8,000 ft.) It is found primarily on slopes above stream drainages in the 1976 study azea, occurring along the • north side of the North Fork of the Gunnison River, on south-facing slopes in Sylvester Gulch, and 2.04-I40 Revised November 2004 PRIO