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2007 RESULTS <br />Precipitation in 2007 was unusually high during the winter and spring. Data from the <br />Arkansas River Basin show that the precipitation from January through June 2007 was <br />7.83. (see Table 1.) This regionally high precipitation is reflected in the cover and <br />production values obtained from the reclaimed areas. <br />A total of 29 transects were sampled; twelve on Pit 4; thirteen on the large Pit 2 contour <br />strip east of the county road; and four on the small Pit 2 contour strip west of the county <br />road. After calculating sample adequacy it was determined that 10 samples were <br />adequate for cover and 28 samples were needed to achieve production sample adequacy. <br />Therefore, sample adequacy was achieved for both cover and production. <br />Cover <br />The average total vegetation cover in 2007 was 44.8% as shown on Table 2. Of this total <br />grasses contributed 17.1%, forbs contributed 24.5%, sub-shrubs contributed 1.7% and <br />shrubs contributed 1.6%. The predominant species was smooth brome, an introduced <br />grass, at 13.8% absolute cover and a relative cover value of 30.7%. Field bindweed was <br />the second most dominant species with 11.2% absolute cover and 25.0% relative cover. <br />Alfalfa contributed 3.9% absolute cover and 8.8% relative cover followed closely by <br />sweet clover at 3.1% absolute cover and 7.0% relative cover. In 2007, 32 species were <br />observed in the cover sampling as shown on the species list in Table 3. <br />Species Composition <br />The total number of plant species encountered during cover sampling was thirty-two. <br />Graminoids accounted for eight species, forbs - twenty species, sub-shrubs - one species <br />and shrubs - three species. Some of these could not be identified in the field. Of the <br />identified species twelve were native and fifteen were introduced. A mix of annual and <br />perennial species was present. There were sixteen perennials, five biennials and eight <br />annual species observed. Seasonality of the reclaimed area species was mixed, both <br />warm and cool season species were present, however only 1.8% of the relative cover was <br />composed of warm season grasses and forbs. Cool season species significantly <br />dominated. <br />The dominant species, Smooth Brome, sweet clover and alfalfa are cool season <br />introduced species commonly used in rangeland pastures. These species were most likely <br />included in the reclamation seed mix. <br />The other dominant species field bindweed is an introduced perennial. It is widespread in <br />cultivated areas, pastures, lawns, gardens, roadsides and waste areas throughout <br />Colorado. Active management would be necessary to eradicate the species. Field <br />bindweed is included on List C of the State's Noxious Weed list. List C species are to be <br />4