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The sagebrush vegetation type as identified within the study area occurs on shallow soil that <br />occurred predominantly in map units 98C and 98D. When the current NRCS soil survey (2013) <br />is overlain on the baseline vegetation map, the SG -1 community occurs on soils 71 <br />(Nyswonger), 76 (Pinon-Bowdish), and 78 (Pinon-Ustic Torriorthents). The native vegetation <br />on these soils is typically a pinyon -juniper dominated woodland or a shrub dominated <br />rangeland. As evidenced by the cover data, and verified by field observations, the <br />pinyon -juniper woodland overstory has been essentially removed. The removal of this <br />overstory plus the level of disturbance associated with livestock use and man's impact has <br />completely altered the composition of the site. Impacts include occasional chaining, and <br />chemical spraying to reduce sagebrush plus poor cattle management practices that has led to <br />most desirable plant species being removed. In evaluating the Guide for Determining Forage <br />Condition attached to the Pinyon -Juniper Woodland Site Description, it is apparent that the <br />sites would only warrant a poor forage condition rating. Note that no woodland site index <br />information has been provided in the Site Description. The stocking rate for the sagebrush type <br />is estimated at a low 0.09 AUM's/ac or 12 acres/AUM assuming use of all grasses and the <br />more palatable forbs. <br />As stated earlier, the sagebrush -1 type represents a remnant native community that has been <br />severely altered because of intensive agricultural land use and associated support activities. <br />Though these sites normally have a pinyon -juniper tree overstory (previously discussed), these <br />have most likely been removed for fencing materials, firewood, land clearing, and from the <br />impacts of high concentrations of grazing animals. Most of the type occurs where it is <br />impractical to irrigate. The pastures are usually heavily stocked at least during part of the year, <br />resulting in a high level of animal pressure from grazing and trampling. The sites are also <br />periodically used as equipment parking, storage, or boneyard areas and winter livestock <br />feeding areas. The shallow soils, rock outcrops, and low natural precipitation, further reduce <br />the potential productivity of the site, while increasing the potential for further deterioration and <br />decreasing the opportunity for any recovery. The majority of species encountered during cover <br />sampling (see Table 2.04.10-21) were increaser or invader species. Consistent with the <br />composition of severely deteriorated native plant communities in the Great Basin and Colorado <br />Plateau regions, cheatgrass, sagebrush, four -wing saltbrush, and broom snakeweed <br />accounted most of the vegetative cover. <br />February 2015 JR -66) 2.04.10-73 <br />