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For statistical purposes, each cover transect (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), soil (bare ground), rock, or litter. Subsequent "hits" on vegetation were <br />also recorded. Cover data were recorded and reported by individual plant species. The <br />first interception was used to calculate total cover values. Additional interceptions were <br />used to calculate relative cover of individual plant species and lifeforms. The quantitative <br />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 production <br />plot was located and randomly oriented at the end of each cover transect. Additional <br />herbaceous quadrats were located randomly as described above. Herbaceous production <br />plots were 0.50 square meters in azea. All current year above ground live herbaceous <br />plant biomass was clipped within the 0.50 square meter quadrat. Perennial grasses, annual <br />grasses, and annual, biennial, and perennial forbs were clipped and bagged to represent <br />total herbaceous production. Succulents, suffrutescent, and woody plants were not <br />sampled. Production material was air dried until weights varied by no more than O. lg. <br />Woody Plant Density <br />Woody plant density was determined through the use of belt transects 50 square meters in <br />area. Woody plant density transects were run beside the cover transects and encompassed <br />• two meters on either side of the 12.5 meter long cover transect. Woody plant density data <br />were collected and reported by species. <br />Species Composition <br />Species composition information was computed from vegetation cover data. Relative <br />cover information provided a basis for evaluation of the importance of each encountered <br />plant species and lifeform. <br />Sample Numbers/Sample Adequacy <br />For the purposes of this baseline sampling, cover sampling was undertaken to sample <br />adequacy. Herbaceous production, being highly variable in the oakbrush understory was <br />sampled to a maximum of fifty quadrats (as agreed to by CDMG). Woody plant density <br />was sampled with fifteen 50 square meter transects. Minimum sample sizes and standazd <br />deviation are reported as an indication of variability of the sampled parameters. <br />Comparisons between sample mean parameter values assume that the sample mean value <br />accurately represents the population mean in all cases. <br />• <br />-5- <br />