2011-01-18_REPORT - C1981041 (2)

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This unit passes the proposed cover, production, and woody plant density standards but fails all but one diversity standard (Table 1). Qualitative analysis indicates that this revegetated area exhibited a stable dominance of shrubs, little herbaceous diversity, and is in fair to average condition overall. 3.4 North Decline Ground cover of the North Decline Area consisted of 58.1% live vegetation, 6.1% rock, 23.5% litter, and bare ground exposure of 12.3% (Table 3a). Perennial cover across the unit averaged 16.4% with annual and biennial cover averaging 41.7 %. Dominant taxa were cheatgrass, greasewood, shadscale, and fourwing saltbush with 37.6 %, 7.1 %, 4.5% and 3.3% average cover, respectively. Current annual herbaceous production in the North Decline totaled 560 pounds per acre with perennials contributing 6 pounds per acre to the total (Table 5a). Woody plant density averaged 1,153 shrubs per acre comprised mostly of fourwing saltbush, greasewood, and big sagebrush (Table 6a). Rubber rabbitbrush and shadscale are scattered throughout the unit. This unit passes the proposed cover, production, and woody plant density standards but fails all but two diversity standards (Table 1). Greasewood and shadscale seedlings were abundant throughout the unit and there is an invasion by big sagebrush on the eastern side of the unit. A majority of the unit has little to no herbaceous perennial cover, as the recent herbicide application and inter - seeding effort appears to be a failure. However, there is a half -acre slice of this unit where perennial grasses have established on the eastern terrace next to the wash. The noxious weeds, jointed goat grass (Aegilops cylindrica) and saltcedar ( Tamarix ramosissima), are proliferating in the central wash (Map 6). 3.5 North Decline Mine Dewatering System Ground cover of the North Decline Mine Dewatering System Area consisted of 45.0% live vegetation, 9.0% rock, 24.5% litter, and bare ground exposure of 21.5% (Table 3a). Perennial cover across the unit averaged 36.7% (up from 27.1% in 2008) with annual and biennial cover averaging 8.3% (down from 23.4% in 2008). Dominant taxa were greasewood, cheatgrass, thickspike wheatgrass (Elymus lanceolatus), and bulbous bluegrass (Poa bulbosa) with 13.1 %, 7.5 %, 6.2 %, and 4.2% average cover, respectively. Current annual herbaceous production in the North Decline Mine Dewatering System Area totaled 632 pounds per acre, with the perennials contributing 510 pounds to forage production (Table 5a). Woody plant density averaged 820 shrubs per acre comprised mostly of greasewood with lesser amounts of fourwing saltbush, rubber rabbitbrush and shadscale scattered throughout the unit (Table 6a). This unit passes all of the proposed revegetation success criteria except only one warm - season grass was observed (proposed standard is two) during sampling within the unit (Table 1). Qualitative analysis CEDAR CREEK ASSOCIATES, Inc. Page 19 Snowcap - Revegetation Evaluation - 2010