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vegetative biomass. Fresh vegetation biomass adequacy calculations determined that a minimum of 25 <br />samples were needed to achieve adequacy. Additional biomass quadrats were harvested until adequacy <br />was achieved. Production standazds aze based on air-dry weight. Plant biomass was dried at 110°F for a <br />minimum of 72 hours to a constant weight then, re-weighed to determine dry biomass production on this <br />site. Paper bag weight was subtracted from biomass calculations. The minimum number of samples <br />required to achieve sample adequacy on the dried vegetation was 20.8 samples. Sample adequacy was <br />achieved for vegetative production. <br />Shrub Density <br />Shrub density data were collected using a belt transect approach. All shrubs occurring within one meter <br />on either side of the 50 foot cover transect line were counted on the basis of species. Stem count was <br />recorded by species and reported as stems per acre. Only two woody species were encountered during <br />the sampling; Four-wing saltbush (Atriplex canescens) and Green rabbitbrush (Chrysothamnus <br />vicidiflorus). Shrub density data was not collected to sample adequacy. <br />Sample Adequacy: <br />Sample adequacy calculations were made for vegetative cover and productivity. The following formula, <br />accepted by the CDMG, was used for these calculations: <br />Nmin t 2 S 2 <br />(d Xear)~ <br />Where: <br />Nm;~ minimum sample size <br />t= the "T" distribution value at the 90% confidence level <br />s= sample standard deviation <br />sZ= sample variance <br />d=percent acceptable deviation from the mean (] 0%) <br />Xbar sample mean <br />Sample adequacy was achieved for vegetation cover and vegetative productivity. Minimum sample size <br />is reported on Tables 2, 3 and 4. <br />Statistical Analysis <br />Separate reference areas of approximately 3 acres in size were established for the two vegetation <br />communities: pinyon juniper and grassland. However, neither reference area can be located currently <br />and were unable to be utilized for comparison purposes during the 2003 sampling period. Therefore, the <br />data collected in 2003 will be compazed to the average of the data collected at the reference areas in <br />1981, obtained from the revegetation plan from the permit submitted October 16, 1981. <br />