2011-01-18_REPORT - C1981041 (2)

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This unit passes a majority of the proposed revegetation success criteria with two exceptions (Table 1): no warm - season grasses were intercepted during sampling (proposed standard > 0.5% composition) and only one species was observed in the unit (proposed standard is 2). Qualitative analysis indicates the revegetation at the Roadside North Portal Facilities - Shadscale is in average condition overall. This area exhibits a diverse shrub population, with most individuals appearing robust and healthy. There is little diversity of grasses in the understory due to the prevalence of cheatgrass. 3.12 Roadside Refuse Borrow Area Ground cover of the Roadside Refuse Borrow Area consisted of 27.9% live vegetation, 4.1% rock, 13.1% litter, and bare ground exposure of 54.9% (Table 3b). Perennial cover across the unit averaged 13.1% (up from 8.4% in 2008) with annual and biennial cover averaging 14.5% (down from 25.7% in 2008). Dominant taxa were cheatgrass, forage kochia, rubber rabbitbrush, and shadscale with 12.8 %, 3.0 %, 2.9 %, and 2.8% average cover, respectively. Current annual herbaceous production in the Roadside Refuse Borrow Area totaled 263 pounds per acre, with perennials contributing 140 pounds to forage production (Table 5b). Woody plant density averaged 761 shrubs per acre comprised mostly of shadscale with lesser amounts of fourwing saltbush, rubber rabbitbrush, and greasewood scattered throughout the unit (Table 6b). This unit passes a majority of the proposed revegetation success criteria with three exceptions (Table 1): only one warm - season grass was observed in the unit, the total herbaceous production was below 90% of the Shadscale Reference Area value of 558 pounds per acre and the unit falls just short of the woody plant density standard of 800 live stems per acre. Qualitative analysis indicates that the Roadside Refuse Borrow area is in average but improving condition overall. The noxious species bindweed (Convolve /us arvensis) was observed within this unit. 3.13 Roadside Refuse Dilwosall Area Ground cover of the Roadside RDA consisted of 44.3% live vegetation, 2.8% rock, 18.1% litter, and bare ground exposure of 34.8% (Table 3b). Perennial cover across the unit averaged 28.4% (up from 27.7% in 2008) with annual and biennial cover averaging 15.9% (down from 29.1% in 2008). Dominant taxa were forage kochia, cheatgrass and greasewood with 25.6 %, 15.8 %, and 1.9% average cover, respectively. Current annual herbaceous production in the Roadside RDA totaled 707 pounds per acre, with the perennials contributing 580 pounds to forage production (Table 5b). Woody plant density averaged 1,331 shrubs per acre comprised mostly of greasewood with lesser amounts of shadscale and fourwing saltbush scattered throughout the unit (Table 6b). CEDAR CREEK ASSOCIATES, Inc. Page 23 Snowcap - Revegetation Evaluation - 2010