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3.1.1 Vegetation Cover <br />Total mean vegetation cover of Reclamation Area 30 was 52.60 percent. Crraminoids <br />provided 49.20 percent mean cover (92.73% relative cover) and forts accounted for 3.40 <br />percent mean cover (7.27% relative cover). The most frequently encountered species were <br />Bromus tectorum (cheatgrass), and Calamovilfa longifolia (prairie sandreed), present in all <br />transects. Oryzopsis hymenoides (Indian ricegrass) was present in 90 percent of transects. <br />Eight species were encountered in four or fewer transects. <br />Within Reclamation Area 30, Bromus tectorum was dominant, with contributions of 23.80 <br />percent mean and 40.30 percent relative cover this growing season. Above average <br />precipitation in April and June 2010 likely contributed to ideal growing conditions for this <br />cool season annual graminoid. Four additional species encountered contributed three or more <br />percent relative cover including; Oryzopsis hymenoides with 13.40 percent mean (32.12% <br />relative cover), Calamovilfa longifolia contributing 8.00 percent mean total and 12.73 <br />percent relative cover, Bouteloua gracilis (blue grams) with 2.20 percent mean cover (4.85% <br />relative cover), and Melilotus officinalis (yellow sweetclover) providing 1.80 and 4.24 <br />percent mean and relative cover, respectively. <br />Vegetative litter (prior years growth and other biologic organic material) comprised 35.00 <br />percent ground cover overall within Reclamation Area 30 this season. Bare soil accounted for <br />12.40 percent of the ground cover. No rock or cryptogams were encountered during the <br />cover sampling this year. <br />3.1.2 Herbaceous Production <br />Total herbaceous production within Reclamation Area 30 was 144.85 g/m2 (1291 lb/ac) this <br />year. <br />3.1.3 Species Composition <br />Cover sampling identified two lifeforms and eleven species within Reclamation Area 30. The <br />lifeforms included five species of perennial grass, two annual grass species, one perennial forb, <br />one biennial forb, and two annual forbs. Of the species encountered in Reclamation Area 30, <br />six were native and five were introduced. Perennial species outnumbered annual species by <br />six to four, with one biennial. Both warm and cool season species contributed to the <br />seasonality of the area. Warm season graminoids outnumbered cool season graminoids by <br />four to three. All forb species encountered were cool season. <br />Reclamation Area 30 had five species contributing greater than three percent relative cover <br />this year. The species contributing greater than three percent relative cover included three <br />perennial grasses, one annual grass, and one biennial forb. These species included the cool <br />season annual grass Bromus tectorum with 40.30 percent relative cover, cool season <br />Oryzopsis hymenoides accounting for 32.12 percent relative cover, the perennial warm season <br />grass Calamovilfa longifolia contributing 12.73 percent relative cover, perennial warm season <br />grass Bouteloua gracilis with 4.85 percent relative cover, and the biennial forb Melilotus <br />officinalis providing 4.24 percent relative cover. <br />Coors Energy Company Keenesburg Mine Page 9 <br />2010 Revegetation Monitoring Report