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communities (predominantly oakbrush and aspen). Old field/pasture vegetation <br />communities are comprised of one vegetative stratum, a low herbaceous layer (<0.5 <br />meters) dominated by graminoids. Figures 2 and 3 provide illustrations of the character <br />of the historic record vegetation community this year. As expected, native and introduced <br />pasture and range grasses dominate the vegetation cover and herbaceous production of the <br />historic record vegetation community. Organic litter from the graminoids provides <br />additional significant cover on the ground surface. <br />4.1 QUANTITATIVE EVALUATION <br />The general composition of the historic record vegetation community was that of a single <br />stratum grassland. The single low herbaceous stratum was composed of herbaceous <br />graminoids and forbs. The dominant graminoid species was the cool season introduced <br />pasture grass Bromus inermis (smooth brome). Agropyron smithii (western wheatgrass), <br />a native cool season bunch/sod former, the cool season naturalized sod forming Poa <br />pratensis (Kentucky bluegrass), the introduced perennial forb Convolvulus arvensis (field <br />bindweed), Erigeron flagellaris (daisy) a native annual forb, and Agropyron intermedium <br />(intermediate wheatgrass), an introduced cool season pasture species were the remaining <br />species which contributed more than three percent relative cover in the historic record <br />vegetation community cover sampling this season. <br />Two lifeforms were encountered during the cover sampling of the historic record <br />vegetation community; graminoids and forbs. Fourteen individual plant species were <br />encountered during cover sampling. Four species were graminoids and ten were forbs. <br />Of the species encountered, nine were perennial, four were annual, and one a biennial. <br />All species encountered were identified as cool season. Six species were native in origin <br />and eight were introduced. The plant species encountered and their characteristics are <br />presented in Table 3. <br />4.1.1 Vegetation Cover <br />Total vegetation cover of the historic record vegetation community was 56.40 percent. <br />Graminoids provided 45.33 percent mean cover (81.49% relative cover) and forbs <br />represented 11.07 percent mean cover (18.51% relative cover). A summary of the cover <br />sampling data is presented in Table 4. The sampling revealed that the cover values were <br />consistent with a standard deviation of 4.61 percent. <br />Graminoids were the predominant life form in the study area. The dominant graminoid <br />species in the study area was Bromus inermis at 32.00 percent mean cover (58.15% <br />relative cover). Agropyron smithii had the third highest total cover value (5.33%) and <br />second highest relative cover, 9.86 percent. Poa pratensis provided 5.47 percent total <br />cover and 8.45 percent relative cover. Two forb species accounted for significant cover <br />(relative cover greater than 3%); Convolvulus arvensis at 4.13 percent mean cover (6.24% <br />relative cover) and Erigeron flagellaris with 3.87 percent mean cover (6.04% relative <br />cover). Agropyron intermedium contributed 2.53 percent mean vegetation cover and 5.03 <br />percent relative cover. Cryptogams (mosses, lichens, and diminutive non-flowering <br />plants) provided 0.13 percent total vegetation cover in the study area. <br />Mountain Coal Company, LLC Page 6 <br />Historic Record Study Area Vegetation Sampling Report: 2010