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• Woody plant densities were measured in the irrigated pasture vegetation type using direct counts from 1 <br />= 500' color aerial photography with field checks for verification. <br />Sample Point Selection - 1999. Individual sample point locations, and belt transect origins were <br />selected using pairs of randomly-generated coordinates. The 1999 vegetation map was brought into <br />ESRI ArcView and a state plane 100 foot interval tic grid was overlaid on the map. Coordinates located <br />within a map unit were listed and exported to Microsoft Access where a random number generator was <br />used to pick pairs of coordinates for sampling locations. The numbers 0 to 359 were also entered into <br />Microsoft Access and a random number generator used to select transect direction. <br />Sample point locations were located from the resultant transects being plotted on the raster digital aerial <br />photo. The observer then walked to that point using visible landmarks. Once the vicinity of the sample <br />point was found, a orange spike was thrown over the observers shoulder to identify the exact location <br />where the sampling point would be located. <br />Vegetation Cover and Frequency - 1999. Quantitative measurements of vegetation cover and plant <br />species frequency were made in the sagebrush - 1 (SG-1), sagebrush - 2 (SG-2), sagebrush reference <br />area, dryland pasture reference area, irrigated pasture and swaleldrainage vegetation types. <br />• Vegetation cover data was collected in the sagebrush type by the point-intercept technique applied by <br />use of an laser point bar. The data was collected on July 13 through 20, 1999. The sampling design <br />consisted of groups of ten points sampled at 10 ft. intervals along a 100 ft. Iransect to achieve 100 points <br />per transect. Thirty to 50 transects were sampled. Each group of ten points., with a 10cm interval <br />between each point, was oriented such that 10 points were projected vertically downward (or upward for <br />overhanging canopy) perpendicular to the transect. At each point, the first contact of a plant species was <br />recorded as a "hit". If the hit was a living perennial, the vegetation was moved to see if a subsequent <br />perennial was "hit" and recorded separately as a second "hit". In cases where vegetation was not <br />contacted, either bare ground (soil), litter, or rock hits were recorded. Each hit represented one percent <br />cover for a transect. For example, a plant species that was contacted 15 times on a transect had an <br />estimated cover of 15 percent for that particular transect ((15/100) x 100). Since the points were <br />situated systematically along the randomly-located transects, each transect (i.e., 100 data points) <br />represented an observation in the sample. Therefore, the estimated mean cover for a particular species <br />in the vegetation type as a whole was derived by summing the percent cover measured on each transect <br />and dividing by the total number of transects sampled. <br />(REVISED 8/15/00) 2.04.1 ~ - 18 <br />