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4.9 Sample Point Selection -1999 Individual sample point locations, and belt transect origins <br />were selected using pairs of randomly -generated coordinates. The 1999 vegetation map was <br />brought into ESRI ArcView and a state plane 100 foot interval tic grid was overlaid on the map. <br />Coordinates located within a map unit were listed and exported to Microsoft Access where a <br />random number generator was used to pick pairs of coordinates for sampling locations. The <br />numbers 0 to 359 were also entered into Microsoft Access and a random number generator <br />used to select transect direction. <br />Sample point locations were located from the resultant transects being plotted on the raster <br />digital aerial photo. The observer then walked to that point using visible landmarks. Once the <br />vicinity of the sample point was found, a orange spike was thrown over the observer's shoulder <br />to identify the exact location where the sampling point would be located. <br />4.10 Vegetation Cover and Frequency - 1999 Quantitative measurements of vegetation <br />cover and plant species frequency were made in the sagebrush - 1 (SG -1), sagebrush - 2 (SG - <br />2), sagebrush reference area, dryland pasture reference area, irrigated pasture and <br />swale/drainage vegetation types. <br />Vegetation cover data was collected in the sagebrush type by the point -intercept technique <br />applied by use of an laser point bar. The data was collected on July 13 through 20, 1999. The <br />sampling design consisted of groups of ten points sampled at 10 ft. intervals along a 100 ft. <br />transect to achieve 100 points per transect. Thirty to 50 transects were sampled. Each group <br />of ten points, with a 10cm interval between each point, was oriented such that 10 points were <br />projected vertically downward (or upward for overhanging canopy) perpendicular to the <br />transect. At each point, the first contact of a plant species was recorded as a "hit'. If the hit <br />was a living perennial, the vegetation was moved to see if a subsequent perennial was "hit' <br />and recorded separately as a second "hit'. In cases where vegetation was not contacted, either <br />bare ground (soil), litter, or rock hits were recorded. Each hit represented one percent cover <br />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 <br />were situated systematically along the randomly -located transects, each transect (i.e., 100 data <br />points) represented an observation in the sample. Therefore, the estimated mean cover for a <br />particular species in the vegetation type as a whole was derived by summing the percent cover <br />measured on each transect and dividing by the total number of transects sampled. <br />February 2015 JR -66) 2.04.10-21 <br />