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<br /> <br /> 4.1.3 Woody Plant Density and Dimensions <br />' <br /> Woody plant densities varied between Test Plots and within Test Plots (Table 29). No <br /> specific patterns emerged from the 1993 sampling. In general, woody plant densities <br />' were highest across treatments on Test Plot 2. This may be linked to aspect and slope, <br /> with the shrub species encountered being adapted to more xeric moisture regimes. Test <br />' Plot 1 exhibited a greater number of woody species encountered on all treatments. The <br />48" treatment had the highest woody plant density of all Test Plot treatments, due <br /> largely to the great number of Chrysothamnus nauseosus seedlings present in the plot. <br /> Atriplex canescens and Atriplex confertifolia were best represented on all treatments of <br />' Test Plot 2. Woody plant densities on Test Plot 2 were closest to or exceeded the <br /> woody plant density success standard of 800 stems per acre. Maximum woody plant <br />' growth, as evidenced by height and diameter (Table 30) differed by species in each <br /> Test Plot. In Test Plot 1, Chrysothamnus nauseosus individuals were the largest in all <br /> treatments except the 48" plot which was dominated by a single large Atriplex <br /> canescens. Test Plot 2 and 3 woody plant height and diameter dominants were the <br /> Atriplex species. <br /> 4.1.4 Species Composition and Diversity <br /> Species diversity information for all areas sampled in 1993 is compiled in Table 31. Of <br />the eight lifeforms represented in sampling, four predominated in all areas; perennial <br /> and annual graminoids, annual forts, and shrubs. Total numbers of species present <br /> were close across all areas ranging from five (Test Plot 3 6") to eleven (Test Plot 1 <br />' 24", Test Plot 3 24", and Shadscale Shrubland Reference Area). Figure 20 graphically <br /> depicts the total number of species encountered by lifeform across all areas. The <br />' number of species are relatively evenly distributed with respect to total species presence <br /> across Test Plots and treatments to prevent any general trend speculation. For <br /> example, while the number of annual grass species is constant (1) across all areas <br />' sampled, perennial grass numbers vary. In Test Plot 1 the number of perennial <br /> graminoids increases with soil depth, while in Test Plots 2 and 3 there are more <br /> perennial grasses on the 12" depth than either the 6" or 24" depth. Shrub numbers <br /> increase with soil depth on Test Plots 1 and 2, but remain constant across increasing <br /> soil depth on Test Plot 3. Subtle environmental or biologic factors are apparently <br />1 affecting species distribution on the Test Plots, precluding speculation on obvious <br />general trends. Figure 21 presents a distribution of lifeforms based on their relative <br /> abundance at each sample location. By eliminating species with relative covers less <br />' than 34'0, a different perspective on species composition is achieved (Figure 22). <br />' S4 <br />