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• the sample point was found, a stake was thrown over the observor's shoulder to identify the <br />exact location where the sampling point would be located. <br />Vegetation Cover and Frequency - 1987. Quantitative measurements of vegetation cover <br />and plant species frequency were made in the sagebrush, irrigated pasture and swale/drainage <br />vegetation types. <br />Vegetation cover data was collected in the sagebrush type by the point-intercept technique <br />applied by use of an optical point bar (Mueller-Dombois and Ellenberg 1974; Viert 1985; <br />Buckner 1985). The data was collected on July 9 and 10, 1987. The sampling design <br />consisted of groups of ten points sampled at 2m intervals along a 20m transect to achieve 100 <br />points per transect. Thirty transects were sampled. Each group of ten points, with a 10cm <br />interval between each point, was oriented perpendicular to the transect such that five points <br />were projected vertically downward (or upward for overhanging canopy) on each opposing side <br />of the transect. At each point, the first contact of a plant species was recorded as a "hit". In <br />cases where vegetation was not contacted, either bare ground (soil), litter, or rock hits were <br />recorded. Each hit represented one percent cover for a transect. For example, a plant species <br />. that was contacted 15 times on a transect had an estimated cover of 15 percent for that <br />particular transect ((15/100) x 100). Since the points were situated systematically along the <br />randomly-located transects, each transect (i.e., 100 data points) represented an observation in <br />the sample. Therefore, the estimated mean cover for a particular species in the vegetation <br />type as a whole was derived by summing the percent cover measured on each transect and <br />dividing by the total number of transects sampled. <br />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 September 15 and 16, 1987. The sampling design consisted of 25 <br />pairs of points, sampled at 1m intervals along a 25m transect to achieve 50 points per transect. <br />A minimum of 15 transects, distributed throughout the type, were sampled. The two points <br />constituting a pair were spaced 1 m apart on opposite sides and perpendicular to the transect. <br />The points were projected vertically downward (or upward if overstory canopy occurred) to <br />record first hit cover of vegetation, rock, litter, or bare ground (soil). Percent cover by plant <br />• (REVISED 9/99) 2.04.10 - 15 <br />