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Perusal of Charts 18 and 20 indicate that the topsoiled treatments (#1, #2, and #3) exhibited a <br />greater perennial cover than the non-topsoiled treatments (#4 and #5) both inside and outside the <br />fence. However, annual grass levels were also greater in the topsoiled treatments. With respect to <br />shrub density, treatment #2 (no grasses in the seed mix) generally exhibited the highest density while <br />treatment #4 (no topsoil with grasses) averaged the lowest densities (see Tables 28 and 29 and Charts <br />44 & 45 and 46 & 47). The composition of mountain big sagebrush (Artemisia bidentab var. vaseyana) <br />and silver sage (Artemisia Cana) were fairly consistent across all the treatments, however bitterbrush <br />(Purshia tridentate) was far more numerous in treatments #2, #3, and #4 than in treatments #1 and <br />#5, <br />Perusal of Charts 22 through 29 and Charts 36 through 43 indicates an apparent effect due to elk <br />and deer browsing on both the populations and size of palatable shrubs. Overall, the average cover of <br />shrubs protected inside the fence is almost twice the average cover of shrubs outside the fence (23.1% <br />vs. 12.4%). In addition, the average density of shrubs inside the fence is substantially above the <br />average density of shrubs outside the fence (7,907 vs. 5,666 shrubs per acre). The differences are more <br />apparent with shrubs of higher palatability, as bitterbrush and Wyoming big sagebrush exhibit almost <br />three times the cover inside the fence versus outside the fence. On the other hand, a less palatable <br />shrub, silver sage, exhibits very little difference in both cover and density with respect to fencing. <br />Perusal of Tables 24 and 25 and Charts 30 through 33 indicates that average shrub cover continues <br />to increase in Treatments #1 and #2 with mixed results on Treatment #3, and a leveling of cover <br />attributable to shrubs in Treatments #4 and #5. The average cover between fenced and unfenced areas <br />was similar until 2002 when the fencing was erected. Since 2002, the cover values from inside the fence <br />have been increasing faster than outside the fence. Peruse! of Tables 28 and 29 and Charts 44 through <br />47 indicates that shrub densities have decreased since initial sampling in 2001. This phenomenon is <br />expected as shrubs become larger and the competition for nutrients, light, and water increases. Also, <br />confidence in the data from CSU's efforts is reduced given the sampling protocol utilized versus that <br />utilized by Cedar Creek. CSU's sampling protocols incorporate a significant component of undetectable <br />sampling error. <br />Based on these preliminary results, it appears that 6 inches of topsoil with either one of the seed <br />mixes has outperformed both the non-topsoil and 20 inches of topsoil treatment with respell to <br />vegetation cover and shrub densities and diversity after five growing seasons. Placing 20 inches of <br />topsoil appears to only benefit annual and perennial grasses and perhaps increases erosional stability. <br />Controlling access by native ungulates appears to noticeably increase cover (maturity) and densities of <br />Rio TI°OO Energy America I Colowyo Mine Page 70 Revegetation Monitoring - 2006 <br />