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Vegetation Community Sample Parameters <br />• Four vegetation parameters were sampled to evaluate the vegetative condition of the <br />study area. Vegetation cover, total herbaceous production, species composition and <br />woody plant density were the parameters for which quantitative data were collected for <br />each vegetation community. <br />Vegetation Cover <br />Vegetation cover was estimated by the use of the point-intercept method. An acuhtr <br />point frame (ESCO Associates) was used to minimize instrument error and maximize <br />precision and observer accuracy. Transect length was determined by the density of the <br />vegetation communities. The oakbrush and aspen communities were very dense, often <br />with significant shrub layers which limited accessibility. The riparian community was <br />a narrow linear community with a more open understory. Cover transects were 12.5 <br />meters in length in the oakbrush and aspen communities, with two sample data points <br />collected at 0.5 meter intervals along the transact on opposite sides of the transact <br />centerline, 1.Sm apart. In the riparian community, cover transacts were 25 meters in <br />length, with two sample data points collected at 1.0 meter intervals along the transact <br />on opposite sides of the transact centerline, 1.Sm apart. Transact direction was <br />established randomly. In no event were transacts allowed to extend within ten feet of <br />community boundaries or disturbed areas (e.g., roadcuts, powerline corridors) to <br />• minimize impacts from "edge effect." <br />For statistical purposes, each cover transact (comprising 50 data points) served as a <br />sample unit. Data points recorded the first vertical "hit" on vegetation (above or below <br />the instrument), bare ground, rock, or litter. Subsequent "hits" on vegetation were also <br />recorded. Cover data were recorded and reported by individual plant species. The first <br />interception was used to calculate total cover values. Additional interceptions were <br />used to calculate relative cover of individual plant species and lifeforms. The <br />quantitative cover data also provided the basis for calculation of species composition. <br />Herbaceous Production <br />Herbaceous production was estimated by the harvest method. One herbaceous <br />production plot was located and randomly oriented at the end of each cover tcansect. <br />Additional herbaceous quadrats were located randomly as described above. Herbaceous <br />production plots were 0.50 square meters in area. All current year above ground live <br />herbaceous plant biomass was clipped within the 0.50 square meter quadrat. Perennial <br />grasses, annual grasses, and annual, biennial, and perennial forts were clipped and <br />bagged to represent total herbaceous production. Succulents, suffrutescent, and woody <br />plants were not sampled. Production material was air dried until weights vaned by no <br />more than O. ig. <br />n <br />U <br />-!r <br />