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West Elk Mine 1982 Dry Meadow Yepetation Community and Reference Area The dry meadow community occurs primarily on the top of the level terraces. The most extensive meadow is located on the uppermost terrace. The meadows and the area selected for the meadow reference area show evidence of discing, drilling and/or interseeding. Interpretation of aerial photographs indicate the lazge affected azea meadow was probably modified by clear-cutting or bulldozing. As such, it should be recognized that these aze artificially created communities. The dry meadow areas characteristically have very low shrub densities except on the margins of the communities where secondary growth and invasion by the oakbrush is evident. Dominant species of the dry meadows aze primarily cool season perennial grasses, specifically western wheatgrass (Agropyron smithii), smooth brome (Bromus inermis), and Kentucky bluegrass (Poa pratensis). Total vegetation cover for the affected area dry meadow community was 40.7 percent. About 71 percent of that cover was contributed by western wheatgrass and smooth brome (Exhibit 32). Common forb species included morning-glory (Convolvulus arvensis), common houndstongue (Cynoglossum o~cinale), and curlycup gtunweed (Grindelia squarrosa). Table 24 Summary: Vegetation Community Parameters (1980.1998) Sam le Size Mean Std. Dev. Nma Total Vegetation Cover Percent Affeced Areas D Meadow 1982 20 40.70 9.63 16 Oakbrush 1980 25 46.24 10.58 14 Oakbrush 1995 15 82.00 5.15 1 Oakbrush 1996 15 80.67 4.25 1 As en 1996 15 83.07 3.69 1 Ri arian 1996 15 84.14 5.63 1 Reference Areas D Meadow 1982 20 46.85 8.77 10 Oakbrush 1980 25 58.64 14.33 16 Herbaceous Production Im ) Affected Areas D Meadow 1982 20 278.86 63.45 15 Oakbrush 1980 32 85.52 21.95 18 Oakbrush 1995 50 17.39 11.24 213 Oakbrush 1996 50 84.40 42.02 70 As en 1996 50 96.66 32.65 32 Ri arian 1996 50 90.02 51.29 91 Reference Areas D Meadow 1982 20 363.91 65.75 9 Oakbrush 1960 40 86.23 28.0 28 Wood Plant Densi Affected Areas Oakbrush 1980 #120m 25 156.8 35.71 14 Oakbrush 1995 #150m 15 106.68 25.9 21 Oakbrush 1996 #150m 35 193.69 44.38 15 As en 1996 #150m 21 122.43 20.55 8 Ri arian 1996 #150m 26 123.42 36.36 25 Reference Areas Oakbrush 1980 35 106.7 28.2 19 Notes: 1. Sam le sizes were established b Nmm or direction of CDMG. In the reference area for the dry meadow community, the total vegetation cover was slightly higher at 46.8 percent (Exhibit 32). The dominant species were also western wheatgrass, smooth brome, 2.04-149 RevisedNavem6er 2004 PRIO