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<br />-5- <br />blue wildrye, mountain brome, and slender wheatgrass. The more <br />common forbs were American vetch, giant hyssop, yarrow, lupin <br />(Lupinus spp.), and bedstraw. Seven shrubs, 5 grasses, and 12 forbs <br />(24 total) comprised [he mountain shrub cover type. The index of <br />diversity value was 0.880. The average litter cover was 25% and the <br />canopy cover for grasses, forbs, and shrubs was 18, 12, and 38 <br />percent respectively, for a total cover of 93 percent. Total <br />production for the mountain shrub type was 1,508 pounds per acre <br />(382, 19 and 1,107 for grasses, herbs and shrubs respectively) and <br />estimated carrying capacity for normal years was 1.0 AUM per acre. <br />Based on expected production in unfavorable and favorable years the <br />estimated ranges for forage production and carrying capacity were <br />1,500 to 3,000 pounds per acre and 0.75 to 1.50 AUM's per acre. <br />(7) Pastureland <br />This cover type comprised 180 acres (10%) of the area to be mined. <br />Its physiographic and soils characteristics were similar [o those of <br />the big sagebrush cover type for most of the area; however, some <br />portions were similar to the meadow cover type. Grasses were <br />predominant species. The most important was smooth brome. IC <br />accounted for 91 percent of the productivity. Other grasses were <br />cheatgrass (Bromus tectorum), and western wheatgrass. The common <br />forbs were thistle and several annuals that consisted of bedstraw <br />(Calium proliferum), tarweed (Nadia glomerata), and knotweed. Three <br />grasses and 3 forbs (6 total) comprised the pastureland type. The <br />index of diversity value was 0.374. The average litter cover was 41% <br />and the canopy cover for grasses and forbs was 41 and 6 percent <br />respectivel}•, for a total cover value of 88 percent. The total <br />production for the pastureland cover type was 1,981 pounds per acre <br />(1,820 and 161 for grasses and forbs, respectively) and the estimated <br />carrying capacity for normal years was 0.75 AUM's per acre. Based on <br />expected production for unfavorable and favorable years the estimated <br />ranges far forage production and carrying capacity were 1,200 to <br />1,800 pounds per acre and 0.6 to 0.9 AUM's per acre. <br />(8) Silver Sagebrush - Pieadow (Artemesia cans) <br />This type does not occur in the area to be mined. It was located in <br />upper flood plains and well drained plains adjacent to drainage <br />channels (6,900 to 6,950 feet elevation) on nearly level co gentle <br />sloping (3°I, slope) topography. The soils are similar to the meadow <br />cover type. The silver sagebrush meadow cover type developed from <br />the meadow cover type because of moisture stress where gully cutting <br />had lowered the water table, or where the meadow cover type had <br />deteriorated near its upper elevational range limit. This cover type <br />contained man}• of the same species as the meadow type; however, grass <br />species were more important here than Che sedges and wire grass found <br />