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Plant Cover. The results obtained from the sampling of the 40 plant cover transects on the <br />Irrigated Pasture predisturbance area are presented in Appendix Table 2.04.10 -9, Irrigated <br />Pasture - Plant Cover. Total plant cover on this site averaged 70.63 percent and litter cover <br />averaged 32.32 percent. <br />Seeded perennial grasses were the dominant plant life form encountered on this site, contributing <br />39.38 percent of the total plant cover and 55.61 percent of the total relative cover found on this <br />site. Perennial forbs contributed 27.83 percent of the total plant cover and 39.40 percent of the <br />total relative cover found on this area. Noxious weeds contributed 8.18 percent of the total plant <br />cover and 11.57 percent of the total relative cover found on this area. Native shrubs contributed <br />0.73 percent of the total plant cover and 1.03 percent of the total relative cover found on this <br />area. Annuals and biennials contributed 0.20 percent of the total plant cover and 0.28 percent of <br />the total relative cover found on this site. Alfalfa, a planted introduced perennial forb was the <br />most dominant plant species encountered, contributing 22.87 percent of the total relative plant <br />cover found on this site. The other dominant plants encountered were: Smooth Bromegrass, Tall <br />Fescue, Orchardgrass and Kentucky Bluegrass which contributed 16.21, 13.27, 12.21 and 5.42 <br />percent, respectively, of the total relative cover on this area. <br />The locations of the 40 cover transects sampled in the Irrigated Pasture predisturbance area are <br />shown on Map 2.04.10 -1, Permit Area Vegetation Map. The sample adequacy calculations in <br />Appendix Table 2.04.10 -2, New Horizon North Mine Area - Sample Adequacy Calculations, <br />document that the number of samples required to describe this site at the 90 percent confidence <br />interval was 2.7 transects. <br />Production. The results obtained from the sampling of 69 production transects on this area are <br />summarized in Appendix Table 2.04.10- 10, Irrigated Pasture - Production. This table shows that <br />the herbaceous forage production equaled 92.18 g /1/4 m or 3,285.3 pounds of air dry -dry forage <br />per acre. Perennial grasses contributed 64.98 g/1 /4 m or 70.49 percent of the herbaceous forage <br />produced. Perennial forbs, contributed 27.20 g/1/4 m or 29.51 percent of the herbaceous forage <br />production. <br />The locations of the 69 production transects sampled for this site are shown on Map 2.04.10 -1, <br />Permit Area Vegetation Map. The sample adequacy calculations in Appendix Table 2.04.10 -2, <br />New Horizon North Mine Area - Sample Adequacy Calculations, document that the number of <br />samples required to describe this site at the 90 percent confidence interval was 41.8 transects. <br />Shrub Density. The shrub density counts obtained from the 15 belt transects sampled in this <br />vegetation type are summarized in Appendix Table 2.04.10 -11, Irrigated Pasture - Shrub <br />Density. The average shrub density was determined to equal 1.63 shrubs per one hundred square <br />meters or 65.9 shrubs per acre. Sandbar Willow, Nutka Rose, Russian Olive, Rubber <br />Rabbitbrush, Siberian Elm and River Hawthorn were the only shrubs encountered. <br />Section 2.04.10 Page 14 November 2011 <br />