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Two vegetation types were tentatively identified in the office using recent aerial <br />photographs. These types were then verified in the field. Maps of the vegetation <br />types ere overlaid with grids. The spacing of the grid covering the Cpi• yon <br />Sunipe~ vegetation type. represented 50 m, while that covering the'-bottom <br />Cvegetation type represented 10 m. The grid intersection points were numbered. A <br />random numbers table was used to select forty specific sampling points for each <br />vegetation type. These sampling points were located in the field. A pointer was <br />spun and the actual sampling plot was established three meters from the point in <br />the direction indicated. A plot 2m2 was ocularly estimated for vegetation cover by <br />species, total vegetation, litter, rock and bare ground. Since some plants may <br />overlie other plants, it was possible for plot totals to exceed 100X. Cover data <br />for each vegetation type were compiled and averaged by species, total vegetation, <br />litter, rock and bare ground. <br />All current year vegetation production within the plot, except trees and cacti, was <br />clipped by species, placed in labeled paper bags and returned to NUS facilities in <br />• Denver. The samples were dried at 105°C for 24 hours and weighed to the nearest <br />0.1 gram. The production data from each vegetation type were compiled by species <br />and total production. <br />Shrub and tree densities were estimated using the point centered quarter method <br />described by Mueller-Dombois and Ellenberg (1974). Points were located at 10 m <br />intervals along 100 m transacts which began at randomly chosen sample points. Ten <br />transacts were sampled in the pinyon-juniper vegetation type and five in the <br />bottomland vegetation type. Density data were compiled for overall tree and shrub <br />density, density by species and frequency by species. <br />Adequate sample size for cover and production were calculated using the following <br />formula: <br />_ 2 2 <br />nmin - t s <br />( <br />• where nmin minimum sample size <br />s = sample standard deviation <br />z = sample mean <br />zzz <br />