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where : <br />Cover <br />nmi„ = minimum sample size <br />t = the "T" distribution value at the 90% confidence level <br />s = sample standard deviation <br />s2 = sample variance <br />d = percent acceptable deviation from the mean (10%) <br />Xbar = sample mean <br />A statistically adequate number of samples were taken. Seventeen transects were run and <br />the sample adequacy formula showed that 13 transects were needed for an adequate <br />number of samples. See Table 1 for the sample results. <br />The average total vegetation cover in 2008 was 28.2% as shown on Table 1. Of this total <br />grasses contributed 14.0%, forbs contributed 14%, and shrubs contributed 0.2%. The <br />predominant species was alfalfa, at 11.8% absolute cover and a relative cover value of <br />41.9%. Intermediate wheatgrass was the second most dominant species with 5.5% <br />absolute cover and 19.6% relative cover. Thickspike wheatgrass contributed 3.5% <br />absolute cover followed closely by Smooth brome contributed 2.1% absolute cover and <br />7.5% relative cover. In 2008, 24 species were observed in the cover sampling as shown <br />on the species list in Table 1. <br />Species Composition <br />The total number of plant species encountered during cover sampling was twenty-four. <br />Grasses accounted for ten species, forbs - thirteen species, and one shrub specie. Some <br />of the species could not be identified in the field. Of the identified species twelve were <br />native and fifteen were introduced. A mix of annual and perennial species was present. <br />There were sixteen perennials, five biennials and eight annual species observed. <br />Seasonality of the reclaimed area species was mixed, both warm and cool season species <br />were present, however only 1.8% of the relative cover was composed of warm season <br />grasses and forbs. Cool season species significantly dominated. <br />The dominant species, Intermediate wheatgrass, Smooth Brome, and sweet clover are <br />cool season introduced species commonly used in rangeland pastures. The grass species <br />were most likely included in the reclamation seed mix.