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The point -intercept technique was also used to collect vegetation cover data in the irrigated <br />pasture type, although the sampling design was modified to accommodate the inherently <br />greater cover found in the type as compared to that encountered in the sagebrush. The <br />samples were collected on July 13 through 20, 1999. The sampling design consisted of 10 <br />points, sampled at 10 ft. intervals along a 100 ft. transect to achieve 100 points per transect. A <br />minimum of 30 transects, distributed throughout the type, were sampled. The 10 points were <br />spaced 10 cm. apart perpendicular to the transect. At each point, the first contact of a plant <br />species was recorded as a "hit". Secondary hits of perennial vegetation was not collected as <br />moving the vegetation disturbed the next adjacent "hit" and would have biased the outcome of <br />first "hit" measurements. In cases where vegetation was not contacted, either bare ground <br />(soil), litter, or rock hits were recorded. Percent cover by plant species, or soil, litter, or rock <br />was calculated by dividing the number of hits on each by the total number of points sampled <br />per transect and expressing the result as a percentage. The estimated mean cover for a <br />particular constituent in the vegetation type as a whole was derived by summing the percent <br />cover measured on each transect and dividing by the total number of transects sampled. <br />Vegetation cover data was collected in the graminoid and forb component of the <br />swale/drainage type using plots and ocular estimates (Cox 1976). The graminoid component <br />comprises approximately 95 percent of the swale/drainage type in the study area and consists <br />of extensive tracts of hydrophytic graminoids. Cattails comprise 3 percent of the <br />swale/drainage type and occur adjacent to stock ponds and in waste ditches and range from <br />less than 0.1 acres to approximately 0.5 acres in size. The data was collected on July 13 <br />through 20, 1999. In keeping with 1987 procedures, a single 50 x 50cm plot (0.25m2) was used <br />for estimating cover at randomly -located sample point. A total of 30 plots were sampled. <br />Ocular estimation involved observation of the vegetation, litter, rock, and bare ground from a <br />vertical perspective within the plot boundaries. The plots were marked with 10cm, 5cm, and <br />2.5cm divisions to facilitate estimates of percent coverage. The cover estimates considered <br />the actual area covered by a particular constituent rather than cover classes or close -fitting <br />polygons, to obtain an estimate of absolute or foliar cover. The estimated mean cover for a <br />particular constituent in the type was derived by summing the cover estimates in each plot and <br />dividing by the total number of plots sampled. <br />February 2015 JR -66) 2.04.10-22 <br />