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z.o <br />• Ten transects were evaluated for success comparison and statistical evaluation purposes. The <br />Snedecor-Cochran sample adequacy formula (Equation 2) was then utilized to determine whether an <br />adequate number of transects were sampled. <br />(2) <br />rz sz <br />Nmin <br />(d X)z <br />Where: <br />Nm;n = required number of transects or quadrats <br />d = desired level of precision (0.1 the level of precision for estimate of the <br />Mean to be within 10 percent of the actual mean) <br />x = sample mean <br />sz = sample variance <br />t = the a = .10 t-table value For a single tailed t-test with n-1 degrees of <br />freedom <br />. Data from the initial 10 transects were used to determine sample size adequacy. Sample adequacy <br />was reached upon completion of 13 transects. <br />2.3 HERBACEOUS PRODUCTION <br />Production for the survey azea was determined by hand clipping 0.5 square meter (m2) quadrats. <br />Quadrat locations were randomly located along each transect. Three production plots were clipped <br />along each transect location. Quadrat locations were determined by first selecting a random number <br />between 1 and 25 from the random numbers table. This number was used to determine the distance <br />(in meters) from the transect's point of origin where the quadrat would be placed. At the specified <br />distance, the quadrat was placed 1 meter to the side of the transect tape, alternating between the left <br />and right sides each time the quadrat was placed. The vegetation was then clipped within the quadrat <br />and was sepazated by forb or grass species. Forbs and grasses were further sepazated into annual, <br />biennial, and perennial life forms. Perennial species classified as noxious weeds in the State of <br />Colorado were further classified as "undesirable." <br />Vegetation samples were weighed in the field and the corresponding "wet" weight was recorded. <br />Using wet weight data, the Snedecor-Cochran sample adequacy formula (Equation 2) was utilized to <br />determine whether an adequate number of quadrats were sampled. Sample adequacy was reached <br />upon completion of 36 quadrats (12 transects). <br />Upon completion of field work, the clipped vegetation was oven dried and reweighed as a field "dry" <br />weight. The dry weights were converted to pounds per acre for each respective sampled azea. The <br />dry weights and wet weights for perennial grasses and perennial forbs were recorded sepazately and <br />Revegnaoon5im'eyRepon-RPr{626)Revl doNSep~ember b, 2001 <br />