2018-08-30_PERMIT FILE - C1982057 (2)

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scientific names, common names, indication of whether the plant is native to Colorado or • introduced and whether the plant is an annual, biennial, or perennial species. Nomenclature follows Weber and Johnson (1979). Species that have been designated as selenium "indicator" species (WDEO, 1981) are indicated, as are plants listed in Colorado as prohibited or restricted noxious weeds (Thornton et al. 1974). It should be noted here that three species of Poa were not separated in the field. Poa pratensis is an introduced grass; Poa agassizensis is a very similar native grass. The morphological distinction between the two is not clear, so some material which would be regarded by some as Poa agassizensis has been included as Poa pratensis. During the process of field work it became apparent the Poa tracyi was present and mixed in with Poa pratensis (and Poa agassizensis). All three have heavily webbed lemmas and their separation in the field was impractical. A71 are being lumped under Poa pratensis. Livestock Carrying Capacity. In the Aspen Woodland, there is about 485 lbs/acre of air dry herbaceous forage available, using an oven-dry to air-dry conversion of 1.11, an assumed average proper use factor of 50 percent, and the herbaceous production data collected during this study. Assuming a 900 lb. air dry mont hly forage requirement for a • cattle animal unit, the cattle carrying capacity in the Aspen Woodland vegetation type is 0.54 animal unit months (AUM's) per acre. For sheep, assuming a monthly forage requirement of 150 lbs. air dry, the carrying capacity is 3.2 AUM's per acre. In the Mixed Brush vegetation type, where the observed herbaceous production was 974 lbs. per acre oven dry, the available air dry forage is 541 pounds per acre. For cattle, this translates to 0.60 AUM's per acre and for sheep the figure is 3.61 AUM's per acre. For the Sagebrush vegetation type, where herbaceous production was observed to be 1,125 165. per acre oven dry, the available forage is 624 165. per acre. For cattle, the corresponding carrying capacity is 0.69 AUM's per acre, while for sheep it is 4.16 AUM's per acre. There was no evidence of grazing observed on the haul road corridor. Since the surrounding land is used as cropland, and gra ze able areas are small and dissected, grazing is a secondary or minimal land use. 30