2011-01-18_REPORT - C1981041 (2)

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This unit passes a majority of the proposed revegetation success criteria with three exceptions (Table 1): no cool- season or warm - season grasses were intercepted during sampling (proposed standard > 0.5% composition for each) and only one warm- season grass species was observed in the unit (proposed standard is 2). Qualitative analysis indicates the Roadside Refuse Disposal Area revegetation is in average to good condition overall. Diversity of grasses and forbs is low, although the shrub population displays good diversity. 3.14 Roadside South Portal Uuaer Diversion Ditch Ground cover of the Roadside South Portal Upper Diversion Ditch consisted of 31.6% live vegetation, 15.7% rock, 8.1% litter, and bare ground exposure of 44.6% (Table 3b). Perennial cover across the unit averaged 8.3% (down slightly from 8.7% in 2008) with annual and biennial cover averaging 23.2% (down from 39.8% in 2008). Dominant taxa were cheatgrass, Russian thistle (Sa /so /a austra /is), forage kochia, and shadscale with 17.1 %, 4.8 %, 4.0 %, and 1.6% average cover, respectively. Current annual herbaceous production in the Roadside South Portal Upper Diversion Ditch totaled 521 pounds per acre, with perennials contributing 136 pounds to forage production (Table 5b). Woody plant density averaged 453 shrubs per acre comprised mostly of shadscale with lesser amounts of fourwing saltbush, greasewood, and big sagebrush scattered throughout the unit (Table 6b). This unit passes a majority of the proposed revegetation success criteria with four exceptions (Table 1): no cool- season or warm - season grasses were intercepted during sampling (proposed standard > 0.5% composition for each) and only one warm - season grass species was observed in the unit (proposed standard is 2). The final failure involved woody plant density which fell short of the 800 stem standard. Qualitative analysis indicates the north portion of this unit is in very good condition with good diversity however the southern section is in poor condition with little diversity and dominance of cheatgrass. The noxious weeds, bindweed and whitetop (Cardaria draba), were observed within the southern portion of this unit. 3.15 South Fan - East Area Ground cover of the South Fan - East area consisted of 40.3% live vegetation, 17.8% rock, 13.4% litter, and bare ground exposure of 28.5% (Table 3b). Perennial cover across the unit averaged 19.9% (up from 17.5% in 2008) with annual and biennial cover averaging 20.4% (up from 14.7% in 2008). Dominant taxa were cheatgrass, fourwing saltbush, Russian wildrye, and greasewood with 18.7 %, 7.0 %, 2.7 %, and 2.3% average cover, respectively. Current annual herbaceous production in the South Fan - East totaled 207 pounds per acre, with the perennials contributing 44 pounds to forage production (Table 5b). Woody plant density averaged 267 shrubs per acre comprised mostly of fourwing saltbush and CEDAR CREEK ASSOCIATES, Inc. Page 24 Snowcap - Revegetation Evaluation - 2010