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nmin = 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 />Cover <br />A statistically adequate number of samples were taken. Eighteteen transects were run <br />and the sample adequacy formula showed that 9.2 transects were needed for an adequate <br />number of samples. See Table 1 for the sample results. <br />The average total vegetation cover in 2009 was 38.3% as shown on Table 1. Of this total <br />grasses contributed 28.0%, forbs contributed 7%, and shrubs contributed 3.3%. The <br />predominant species was thickspike wheatgrass at 10.2% absolute cover and a relative <br />cover value of 26.7%. Western wheatgrass was the second most dominant species with <br />6.9% absolute cover and 18.1% relative cover. Intermediate wheatgrass contributed <br />4.3% absolute cover. Forbs contributed 7.0 % absolute cover and 18.3% relative cover. <br />No forb was overly dominant, but the highest cover values were alfalfa, mullein, musk <br />thistle and annual mustard. Three woody plants were observed: four wing salt brush, <br />ponderosa pine and Wood's rose. Absolute cover for woody plants was 3.3% with a <br />relative cover of 8.6%. In 2009, 30 species were observed in the cover sampling as <br />shown on the species list in Table 2. <br />Species Composition <br />The total number of plant species encountered during cover sampling was thirty. Grasses <br />accounted for ten species; forbs accounted for seventeen species, there were two shrub <br />species and one tree. Some of the forb species could not be identified in the field. A mix <br />of annual and perennial species was present. There were eighteen perennials, four <br />biennials and six annual species observed. Seasonality of the reclaimed area species was <br />mixed, both warm and cool season species were present; however there were no warm <br />season grasses observed in 2009 and only one warm season biennial. Cool season <br />species significantly dominated. <br />The dominant species, thickspike wheatgrass, western wheatgrass and intermediate <br />wheatgrass are cool season species commonly used in rangeland pastures. The grass <br />species were most likely included in the reclamation seed mix.