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species, or soil, litter, or rock was calculated by dividing the number of hits on each by the total <br />number of points sampled per transect and expressing the result as a percentage. For <br />example, a species with 2 hits on a transect had a cover of 4 percent ((2/50) x 100). The <br />estimated mean cover for a particular constituent in the vegetation type as a whole was derived <br />by summing the percent cover measured on each transect and dividing by the total number of <br />transects sampled. <br />Vegetation cover data was collected in the graminoid component of the Swale/drainage type <br />using plots and ocular estimates (Cox 1976). The graminoid component comprises <br />approximately 80 percent of the Swale/drainage type in the study area and consists of <br />extensive tracts of hydrophytic graminoids surrounding isolated monotypic islands or stringers <br />of cattail. The cattail islands and stringers range from less than 0.1 acres to approximately 2.0 <br />acres in size. The data was collected on July 21 and 22, 1987. At each randomly-located <br />sample point, a single 50 x 50cm plot (0.25m~) was used. 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 />The remainder of the Swale/drainage type consists of a scrub/shrub component dominated by <br />virtually inpenetrable thickets of willow. The thickets comprise approximately 20 percent of the <br />Swale/drainage type, existing as islands or stringers of vegetation within the graminoid <br />component. The majority of the islands and stringers of willow range in size from <br />approximately 0.1 to 0.25 acres. One stand, located in Swale/drainage vegetation on the west <br />side of the proposed permit area is larger (approximately 2.5 acres in size). Only qualitative <br />estimates of herbaceous and shrub cover were made in this component due to its inherent <br />immeasurability and the lack of pertinent information that would be achieved from quantitative <br />sampling attempts. <br />. (REVISED 9/99) 2.04.10 - 16 <br />