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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), 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 transect. <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 fortis 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 varied by no <br />more than O. lg. Results are reported as grams per square meter. <br />Woody Plant Census <br />Woody plants do not form a significant component of the study azea vegetation. <br />Sampling woody plant density through the use of parametric sampling techniques would <br />be inappropriate given the low numbers of woody plants. to order to quantify and <br />describe the woody plant component within the study area, a complete census of the <br />woody plants present within the study area vegetation community was undertaken. The -- <br />census counted all woody plants within the study area by species. <br />Species Compositiou <br />Species composition information was derived from quantitative vegetation cover data. <br />Relative cover information provided a basis for evaluation of the importance of each <br />encountered plant species and lifeform. <br />Sample Numbers/Sample Adequacy <br />Sample adequacy was calculated for vegetation cover and herbaceous production. For <br />the purposes of this study, vegetation cover and herbaceous production sampling was <br />undertaken to sample adequacy. A minimum of fifteen samples per parameter were <br />taken. Parameters were tested at the 9040 confidence level. Calculated minimum <br />sample numbers and standard deviations are reported as an indication of variability of <br />the sampled parameters. Comparisons between sample mean parameter values assume <br />that the sample mean value accurately represents the population mean in all cases. The <br />following formula was used for sample adequacy calculations: <br />-4- <br />