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3.1.1.1 Vegetation Cover <br />Total vegetation cover of the 1998, 1999, and 2000 reclamation areas was 60.96 percent. <br />Graminoids provided 41.30 percent mean cover (70.43% relative cover) and forbs accounted <br />for 19.30 percent mean cover (28.77% relative cover). Succulents contributed 0.09 percent <br />total cover (0.12% relative cover), while shrubs provided 0.26 percent vegetation cover <br />(0.67% relative cover). The lowest total vegetation cover of the parcels sampled was found <br />in Area 2 (42%) and the highest cover (82%) was found in Area 9. Calamovilfa longifolia <br />(prairie sandreed) was encountered in all cover transects. Bromus tectorum (cheatgrass) was <br />encountered in 89 percent of the transects, Ambrosia psilostachya (ragweeed) in 76 percent <br />of the transects, and Helianthus annuus (annual sunflower) in 67 percent of transects. <br />Calamovilfa longifolia, a warm season native perennial prairie grass was the dominant plant <br />species with total mean vegetation cover of 18.35 percent and 31.17 percent relative cover in <br />the 1998, 1999, and 2000 reclamation areas. Eight additional species contributed significantly <br />to vegetation cover (greater than 3% relative cover); the cool season introduced annual grass <br />Bromus tectorum with 8.30 percent mean cover and 11.84 percent relative cover, the native <br />cool season perennial forb Ambrosia psilostachya contributed 5.26 percent mean cover <br />(8.04% relative cover), the annual warm season native forb Helianthus annuus accounted for <br />5.04 percent total mean vegetation cover (7.48% relative cover), the warm season native <br />perennial grass Panicum virgatum (switchgrass) provided 3.30 percent total mean vegetation <br />cover and 7.12 percent relative cover, cool season native graminoid Agropyron smithii <br />(western wheatgrass) accounted for 3.87 percent mean cover (6.56% relative cover), Kochia <br />scoparia (kochia), the introduced annual forb, contributed 3.43 percent total cover (4.91% <br />relative cover), the warm season perennial native Bouteloua gracilis (blue grama) provided <br />2.30 percent mean total cover (4.29% relative cover), and the warm season perennial native <br />range grass Andropogon hallii (sand bluestem) accounted for 2.13 percent mean cover <br />(4.05% relative cover). <br />Vegetative litter (prior years growth, dead wood, and other biologic organic material) <br />comprised 25.17 percent ground cover overall within the 1998, 1999, and 2000 reclamation <br />areas. Bare soil comprised 13.87 percent of the ground cover. No rock was encountered <br />during the cover sampling in the reclamation areas. Cryptogams provided 0.04 percent <br />ground cover. <br />3.1.1.2 Herbaceous Production <br />Mean total herbaceous production within the 1998, 1999, and 2000 reclamation areas in 2009 <br />was 261.13 g/m2 (23281b/ac). <br />3.1.1.3 Species Composition <br />Cover sampling identified four lifeforms and thirty-six species within the 1998, 1999, and <br />2000 reclamation areas. The lifeforms included sixteen species of perennial grass, two <br />annual grass species, four perennial forbs, one biennial forb, eleven annual forbs, one <br />succulent, and one shrub. Of the species encountered during cover sampling, twenty-six were <br />native and ten were introduced. Perennial species outnumbered annual species by twenty-two <br />Coors Energy Company Keenesburg Mine Page 9 <br />Areas 2, 5, 6, 7, 9, 10, 15, 16, and 19 Vegetation Study (2009)