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• Woody plant density was measured as opposed to shrub density because of the occurrence of <br />subshrubs and the occasional presence of tree species in the type. Succulents were not <br />included in the density calculations. Mean density for the type was 73.4 stems/50m2 or 5,945 <br />stems/acre (Table 2.04.10-13). Basin big sagebrush dominated with an average density of 38.9 <br />stems/50m2 (3,150.9 stems/acre) and a frequency of 100 percent. Indicative of the deteriated <br />state of this type, broom snakeweed had a measured density of 27.7 stems/50m2 (2,243.7 <br />stems/acre). Other species of importance were rubber rabbitbrush (Chrysothamnus nauseosus) <br />and fourwing saltbush (Atriplex canescens) at 4.6 stems/50m2 (372.6 stems/acre) and 1.0 <br />stems/SOm2 (81.0 stems/acre), respectively. <br />A total of 86 species occurred in the sagebrush type (Peabody Appendix 10-1 ), making it the <br />most diverse type studied. Of this total, 36 species occurred in the cover samples, however, only <br />11 species had relative cover values of 1 percent or greater. Grasses (including annuals) <br />comprised 14 of the species (see Table 2.04.10-11), while annual/biennial/perennial forbs totaled <br />15. Four shrubs occurred in the cover samples, as did one succulent and two trees. <br />• The sagebrush vegetation type as identified within the study area occurs on soils of the <br />Travessilla-Pinon channery sandy loam complex (see Peabody Attachment 9-5). Within the <br />complex are small inclusions of Progresso loam soils. No range sites are identified for the <br />Travessilla or Pinon soils because the native vegetation on these soils is typically a <br />pinyon-juniper dominated woodland (see Peabody Appendix 10-3). As evidenced by the cover <br />data, and verified by field observations, the pinyon-juniper woodland overstory has been <br />essentially removed. The removal of this overstory plus the level of disturbance associated with <br />livestock use and man's impact has completely altered the composition of the site. In evaluating <br />the Guide for Determining Forage Condition attached to the Pinyon-Juniper Woodland Site <br />Description, it is apparent that the sites would only warrant a poor forage condition rating. Note <br />that no woodland site index information has been provided in the Site Description. The <br />Progresso soils within the complex are not mapped out because of the small size of these <br />inclusions, and hence the locations of the applicable semidesert loam, range site cannot be <br />identified. The stocking rate for the sagebrush type is estimated at a low 0.09 AUM's/ac or 12 <br />acres/AUM assuming use of all grasses and the more palatable forbs. <br />• (REVISED 8/15/00) 2.04.10 - 43 <br />