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The point-intercept technique was also used to collect vegetation cover data in the irrigated pasture type, <br />• although the sampling design was modified to accommodate the inherently greater cover found in the <br />type as compared to that encountered in the sagebrush. The samples were collected on July 13 through <br />20, 1999. The sampling design consisted of 10 points, sampled at 10 ft. intervals along a 100 ft. transect <br />to achieve 100 points per transect. A minimum of 30 transects, distributed throughout the type, were <br />sampled. The 10 points were spaced 10 cm. apart perpendicular to the transect. At each point, the first <br />contact of a plant species was recorded as a "hit". Secondary hits of perennial vegetation was not <br />collected as moving the vegetation disturbed the next adjacent "hit" and would have biased the outcome <br />of first "hit" measurements. In cases where vegetation was not contacted, either bare ground (soil), litter, <br />or rock hits were recorded. Percent cover by plant species, or soil, litter, or rock was calculated by <br />dividing the number of hits on each by the total number of points sampled per transect and expressing <br />the result as a percentage. The estimated mean cover for a particular constituent in the vegetation type <br />as a whole was derived by summing the percent cover measured on each transect and dividing by the <br />total number of transects sampled. <br />Vegetation cover data was collected in the graminoid and forb component of the Swale/drainage type <br />using plots and ocular estimates (Cox 1976). The graminoid component comprises approximately 95 <br />percent of the Swale/drainage type in the study area and consists of extensive tracts of hydrophytic <br />• graminoids. Cattails comprise 3 percent of the swaleldrainage type and occur adjacent to stock ponds <br />and in waste ditches and range from less than 0.1 acres to approximately 0.5 acres in size. The data <br />was collected on July 13 through 20, 1999. In keeping with 1987 procedures, a single 50 x 50cm plot <br />(0.25m') was used for estimating cover at randomly-located sample point. A total of 30 plots were <br />sampled. Ocular estimation involved observation of the vegetation, litter, rock, and bare ground from a <br />vertical perspective within the plat boundaries. The plots were marked with 10cm, 5cm, and 2.5cm <br />divisions to facilitate estimates of percent coverage. The cover estimates considered the actual area <br />covered by a particular constituent rather than cover classes or close-fitting polygons, to obtain an <br />estimate of absolute or foliar cover. The estimated mean cover for a particular constituent in the type <br />was derived by summing the cover estimates in each plot and dividing by the total number of plots <br />sampled. <br />The remainder of the Swale/drainage type consists of virtually impenetrable thickets of willow. The <br />thickets comprise approximately 2 percent of the Swale/drainage type, existing primarily along the CC <br />Ditch. The majority of the willow type ranges in size from approximately 0.1 to 1 acres. In keeping with <br />1987 procedures, only qualitative estimates of herbaceous and shrub cover were made in this <br />component due to its inherent immeasurability and the lack of pertinent information that would be <br />achieved from quantitative sampling attempts. <br />• (REVISED B/15/00) 2.04.10 - 19 <br />