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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 <br />38.9 stems /50m2 (3,150.9 stems /acre) and a frequency of 100 percent. Indicative of the <br />deteriated state of this type, broom snakeweed had a measured density of 27.7 stems /50m2 <br />(2,243.7 stems /acre). Other species of importance were rubber rabbitbrush (Chrysothamnus <br />nauseosus) and fourwing saltbush (Atriplex canescens) at 4.6 stems /50m2 (372.6 stems /acre) <br />and 1.0 stems /50m2 (81.0 stems /acre), respectively. <br />A total of 86 species occurred in the sagebrush type (Attachment 2.04.10 -5, formerly Peabody <br />10 -1), making it the most diverse type studied. Of this total, 36 species occurred in the cover <br />samples, however, only 11 species had relative cover values of 1 percent or greater. Grasses <br />(including annuals) comprised 14 of the species (see Table 2.04.10 -11), while <br />annual /biennial /perennial forbs totaled 15. Four shrubs occurred in the cover samples, as did <br />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 Attachment 2.04.10 -9, formerly Peabody <br />Attachment 9 -5). Within the complex are small inclusions of Progresso loam soils. No range <br />sites are identified for the Travessilla or Pinon soils because the native vegetation on these <br />soils is typically a pinyon juniper dominated woodland (see Attachment 2.04.10 -7, formerly <br />Peabody Appendix 10 -3). As evidenced by the cover data, and verified by field observations, <br />the 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. 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 Progresso soils within the complex <br />are not mapped out because of the small size of these inclusions, and hence the locations of <br />the applicable semidesert loam, range site cannot be identified. The stocking rate for the <br />sagebrush type is estimated at a low 0.09 AUM's /ac or 12 acres /AUM assuming use of all <br />grasses and the more palatable forbs. <br />Revised September 2010 (PR 06) 2.04.1048 <br />