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were typically removed mechanically or by flooding, and plant species desired for livestock forage <br />were seeded including perennial grasses and forbs such as alfalfa and clover. These irrigated <br />pastures are intended primarily to provide winter forage for livestock, and secondarily to provide <br />cut hay. Uneven application of flood - applied water is typical because of variable terrain, and wet <br />areas soon become dominated by wetland grasses and forbs, and sometimes Russian -olive or <br />emergent wetland plants such as cattail or bulrushes. Weedy annual forbs and cheatgrass <br />typically become established on drier sites, and many become dominant in disturbed areas. The <br />species composition and ecological condition of pre -mine irrigated pastures in the permit area <br />varies widely depending on irrigation water availability and management history. <br />A comparison of the 2007 vegetation data in the reference area with pre -mine studies conducted <br />by Peabody Coal Company in 1987 and WFC in 1999 (in Attachment 2.05.4(2)(e) -5) and <br />Attachment 2.05.4(2)(e) -2) shows that the reference area vegetation is similar to pre -mine <br />vegetation in the irrigated pasture type. The 1987 total vegetation cover was 71.8% and <br />dominated by perennial graminoids, mostly seeded pasture grasses with Kentucky bluegrass the <br />most dominant, all similar to the 2007 reference area measurements. See Table 2.05.4(2)(e) -3. <br />Mean herbaceous production was measured at 2,823 lb/acre, similar to the 2007 reference area <br />mean. <br />In 1999, estimates of mean cover in 2 subjectively selected irrigated pastures (deemed <br />representative of "typical' conditions) were also similar, showing perennial grass cover of 44.5 %, <br />perennial forb cover of 33.3 %, and total desirable vegetation cover of about 79 %. Annual <br />herbaceous production was estimated at 4,153 lb/acre. The 1999 mean is higher than the 2007 <br />mean measured in the reference area, but the irrigated pasture type has been demonstrated in <br />1987 and 1999 sampling to be extremely variable in production depending on site factors, <br />management, and maintenance. <br />The site has been inspected by the NRCS and found to be acceptable as a reference area <br />(Revised: PR -06) 2.05.4(2)(e) - 29 <br />