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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 varied by no <br />more than O. lg. Results are reported as grams per square meter. <br />Woodv Plant Density <br />Woody plants do not form a significant component of the study area vegetation. <br />Sampling woody plant density through the use of parametric sampling techniques would <br />be inappropriate given the paucity of woody plants. In order to quantify and describe <br />the woody plant component within the study area, a complete census of the woody <br />plants present within the study area vegetation community was undertaken. The census <br />counted all woody plants within the study area by species. Woody plants within six <br />feet of the obvious edge of the study area were not counted. <br />Species Composition <br />Species composition information was derived from vegetation cover data. Relative <br />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 sampling, vegetation cover and herbaceous production sampling <br />was undertaken to sample adequacy. A minimum of fifteen samples per parameter <br />were taken. Parameters were tested at the 90% confidence level. Calculated minimum _ <br />sample number and standard deviation are reported as an indication of variability of the <br />sampled parameters. Comparisons between sample mean parameter values assume that <br />the sample mean value accurately represents the population mean in all cases. The <br />following formula was used for sample adequacy calculations: <br />(t)z (s)'` <br />nmin = -------------- <br />(d Xbar)2 <br />where: nmin =minimum sample size <br />t =the Student's t distribution value at the 90% confidence level <br />s =sample standard deviation (s)2= sample variance <br />d =percent acceptable deviation from the mean (10%) <br />Xbar =sample mean <br />-11- <br />