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collected in 2003 will be compared to the average of the data collected at the <br />reference areas in 1981 and the pre-mine data, obtained from the revegetation <br />plan from the permit submitted October 16, 1981. <br />III. Results and Discussion <br />Cover <br />2003 vegetative cover data on the reclaimed New Pryor Mine area was 30.93%, <br />which exceeds 90% of the cover standard established by the Division (20.7%). <br />Data are presented in Table 2. Vegetative cover measured in 2003 showed a <br />marked increase from the 8.93% vegetative cover measured in 2002. This <br />increase shows that the reclaimed community is self-sustaining and can recover <br />from severe stress experienced during the drought of 2002. Litter accounted for <br />an additional 21.47% non-living cover, and rock cover added another 1.6%. <br />Total oflive-vegetation, litter and rock was 54%. Observation of the mine site <br />shows a minimum of erosional features, which would indicate that the 54% total <br />cover is adequate to control erosion. <br />Twenty-four species were recorded during the cover sampling. Species found <br />are shown on Table 1. The twenty-four species consist of seven perennial <br />graminoids, nine perennial forbs, and eight annual or biennial species. Perennial <br />grasses combined made up 9.2% cover (29.7% relative cover). Perennial forbs <br />comprised 15.86% vegetative cover (51.3% relative cover), while annuals and <br />biennials made up 5.9% vegetative cover (19.1% relative cover). Six species <br />contributed greater than 3% relative cover each. Those six species were; <br />Western wheatgrass (10.78% relative cover), Smooth brome (10.34% relative <br />cover) Green needle-grass (3.88% relative cover), Scarlet globemallow (6.47% <br />relative cover), Field bindweed (40.09% relative cover), and red-stem filaree <br />(13.79% relative cover). <br />Species Composition <br />Sixteen perennial species were encountered, seven grasses and nine forbs. <br />One forb, field bindweed (Convo/vulus arvense), is considered a weedy species <br />on the Colorado state weed list but is not considered a noxious weed in Huerfano <br />County. Though not a preferred species, field bindweed has benefits for erosion <br />control and can provide shade cover for seedling establishment of preferred <br />species. Field bindweed is not considered noxious or toxic to livestock. <br />Of the seven perennial grass species measured, only one species, Smooth <br />brome, is considered introduced. All others are native species. Three perennial <br />grass species are considered warm season and four are cool season. Sampling <br />occurred relatively early in the growing season for the warm season species. <br />The timing of the sampling favored the cool season species. Two cool season <br />grass species, Agropyron smithii (Western wheatgrass) and Bromus inermis <br />6 <br />