2004-12-07_PERMIT FILE - C1984063

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• Veoetation - Final Survey. Random sampling was used so that statistical reliability can be achieved. By using a random design, an unbiased estimate of the mean and variance of the vegetation characteristics can be obtained. Also, sampling during the growing season is utilized so that the baseline cover is obtained. Vegetation cover was measured using a line-point method. Transect locations within each land parcel were randomly placed by overlaying a transparent acetate grid of 1/4-inch squares on a map of the study site and selecting horizontal and vertical coordinates of the locations using a random number table. Twenty transect locations were established, eleven in one parcel and nine in the other, before sampling worK began. Locations are shown on Map HGP-11: Vegetation Map. Because both parcels of the study area are comprised of the same sagebrush vegetation type, sampling from both parcels was combined to demonostrate statistical sample adequacy. At each transect location, a metal post was driven into the soil. From that post a fifty-foot metal tape was stretched parallel to the ground at four feet above the ground to another metal past. The direction of each transact was randomly determined, and directions which caused substantial • portions of the transect tine to fall over roads, dirt piles or trash were reJVCted. At fifty one-foot intervals along each transect line, a long metal pin was projected vertically from the tape until a first "hit" was made. Hits were recorded as either plant species, rock. litter, or bare ground. All twenty transect locations were sampled. The more complete vegetation survey was completed in July 1984 on the two areas that are planned for disturbance Csee Map HGP - 11: Vegetation Map). Table 14: (Relative Frequency of Occurrence of Plant Species) shows relative frequency of occurrence of plant species based on transect data. In addition, other species noted in the study area are shown in this table and designated with the letter "T" (trace). These species were not detected under the transects, and their occurrence is not included in the calculation of mean vegetation cover. The predominant species in terms of total vegetation cover is big sagebrush. Although height measurements were not made, it was noted that many individul sagebrush plants are over six feet tall in both areas. Densities are also high enough to make walking through both areas difficult. Three predominant understory species are yellow sweetclover, rabbitbrush, and cheatgrass. Only one other species, bottlebrush aquirreltail, showed more than one percent 79 Revised 5/87