2011-01-18_REPORT - C1981041 (2)

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3.0 RESULTS Tabular compilations of raw data and summaries for the aforementioned sampling efforts are presented in Appendix A on Tables 2 through 57 and Charts 9 through 12. Summaries of the proposed success comparisons for the 17 units individually and collectively are provided on the following pages in Table 1 and Charts 1 through 6. Table 1 gives a quick indication of the overall success of the various revegetation units compared with reference area data and / or standards. With regard to plant cover, all 17 areas sampled in 2010 pass the proposed success comparison (90% of the reference area value) for perennial lifeforms ground cover. With regard to diversity, three of the 17 revegetated areas analyzed pass all seven proposed standards. Ten of the remaining 14 pass at least five of the seven standards. Most of the diversity failures are due to insufficient cover by perennial, warm - season grasses (see Table 1) that are difficult to establish with the high levels of cheatgrass in the surrounding area. The current annual production success comparison follows a similar pattern to that of ground cover. Nine of the 17 sites pass the total production standard (90% of the reference area value) with most of the eight failures due to lack of cheatgrass in sufficient quantities to compare with the reference areas. Woody plant density, on most units, far exceeds the standard of 800 live stems per acre, however, there are three units that do not pass the standard. Treating individual units as a whole is the preferred methodology for bond release evaluation as explained in detail in Appendix B. Included in Table 1 is an acreage — weighted combination of all the units required to be compared with the Greasewood Reference Area and likewise, a combination of all the units required to be compared with the Shadscale Reference Area. When individual units are combined, all success criteria are passed for both comparison aggregates (Shadscale and Greasewood). However, in the interest of full disclosure, the following sections provide a brief narrative of the sampling results for each of the individual revegetated and reference units. 3.1 Cameo Borrow Area No. 1 Ground cover of the Cameo Borrow Area No. 1 consisted of 57.0% live vegetation, 4.0% rock, 23.4% litter, and bare ground exposure of 15.6% (Table 3a). Perennial cover across the unit averaged 25.4% (down from 29.2% in 2008) with annual and biennial cover averaging 31.6% (up from 24.8% in 2008). Dominant taxa were cheatgrass (Anisantha tectorum), fourwing saltbush (Atriplex canescens), greasewood (Sarcobatus vermiculatus), and Palmer penstemon ( Penstemon palmeri) with 30.1 %, 19.7 %, 1.6 %, and 1.5% average cover, respectively. Current annual herbaceous production in the Cameo Borrow Area No. 1 totaled 528 pounds per acre with perennials contributing 108 pounds per acre (Table CEDAR CREEK ASSOCIATES, Inc. Page 12 Snowcap - Revegetation Evaluation - 2010