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summary data from 2007 vegetation sampling, and scientific names of plants). Desirable <br />perennial forbs are much less common, and include mainly Alsike clover with minor amounts of <br />dandelion. In shallow drainageways the soil is saturated during the growing season and wetland <br />plants dominate primarily various species of sedge and rush with minor amounts of tufted <br />hairgrass, buckhorn plantain, common plantain, and rarely cattail. <br />In June 2007, mean cover of total vegetation measured at 15 transects was 71.9% (see <br />Attachment 2.05.4(2)(e) -5). Most of the remaining cover was litter, with very little bare ground <br />(3.5 %). Most of the vegetation is desirable (perennial grasses, grass -like plants, and forbs, <br />excluding noxious weeds), comprising 68.6% cover. Of these, Kentucky bluegrass and tall fescue <br />contribute nearly 48% relative cover (the fraction of total vegetation cover), and sedges, rushes, <br />and wheatgrasses comprise 32% relative cover. Among life forms, desirable perennial grasses <br />(including sedges and rushes) are dominant by far (64% cover, 89% relative cover), and desirable <br />perennial forbs (primarily Alsike clover) are next (4.5% cover, 6.2% relative cover). Undesirable <br />species together comprise total cover of 3.3% and relative cover of 4.6 %. These include shrubs <br />(gumweed), a few weedy annual forb species, and the noxious weed field bindweed; each of these <br />life forms contributes 1.5% or less total cover. <br />Mean total production measured in June 2007 at 44 plots was 2,677 lb/acre for all vegetation, and <br />2,513 lb/acre for desirable vegetation. Perennial grasses (including sedges and rushes) contribute <br />most of the production, at 2,436 lb/acre (97% of desirable production and 91 % of total production). <br />Forbs made up most of the remaining plant production, with a minor contribution from shrubs <br />(gumweed) and the noxious weed species field bindweed. <br />The reference area pasture is in good ecological condition. Soil erosion is minimal, there are no <br />significant gullies or rills, and very little bare ground. Desirable plant species composition is <br />diverse, which provides a robust vegetation stand able to resist some variability in irrigation water <br />application or grazing regimes. Some drier areas tend to be dominated by weedy annual forbs, <br />gunweed, and occasionally cheatgrass, but these areas make up only a small fraction of the <br />reference area, and are typical of flood- irrigated pastures in the Nucla area. <br />The reference area vegetation is representative of the pre -mine irrigated pasture type in the permit <br />area. Irrigated pastures in the permit area were originally mostly dominated by native sagebrush <br />shrublands or pinyon juniper woodlands. When converted to irrigated pasture, trees and shrubs <br />PR -06 June 2010 2.05.4(2)(e) - 27 <br />