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3.0 Results • nutrient deficiencies, grazing, and successional stage. The results of the soil analysis (Section 3.4) indicate that soils aze deficient in nitrogen, phosphorus, and in some cases, potassium. Such deficiencies can reduce plant establishment and plant vigor, resulting in a reduced percentage of vegetation cover. The Survey Area also has been grazed by domestic livestock. However, no evidence of domestic livestock grazing was observed at the Reference Area. Grazing can have different effects on different species. In some cases, grazing pressure can increase the presence of a species (increasers), while other plants respond to grazing by decreasing on a range (decreasers). Several species included in the seed mixture for the Survey Area aze decreasers, including mountain biome (Bromus carinatus), green needlegrass (Stipa viridula), Indian ricegrass (Oryaopsis hymenoides), sand dropseed (Sporobolus cryptandrus), and winterfat (Krascheninnikovia Janata). None of these species accounted for more than five percent of the mean relative cover in the Survey Area. Finally, there is some evidence that the Reference Area is in a later successional stage compared to the Survey Area. For example, blackroot sedge (Carex filifolia) was commonly observed in the Reference Area. The presence of blackroot sedge along with blue gramma and needle and thread grass, as observed in the Reference Area, is often considered indicative of a climax shortgrass community. Climax communities often have an overall higher percentage of cover compared to recently disturbed plant communities. The overall percentage cover of blue gramma is also commonly higher in climax communities. • 3.2 HERBACEOUS PRODUCTION Herbaceous production is summarized in Table 7 for the Survey Area and in Tables S (2001 data) and 9 (1999 data) for the Reference Area. Table 10 provides a statistical summary of productivity data for the Survey Area and Reference Area. Total herbaceous production in the Survey Area was 31 grams (g)/m5 (288 pounds/acre), compazed to approximately 53 grams/m5 (492 pounds/acre) for the Reference Area in 1999 and approximately 34 g/m5 (313 pounds/acre) for the Reference Area in 2001. Total grass production in 1999 at the Reference Area was approximately 20 percent higher than grass production in the Survey Area in 2001. However, in 2001, grass production in the Reference Area was only 8 percent higher than the Survey Area. Productivity ofperennial forbs at the Survey Area were also lower than perennial forb production in the Reference Area in both 1999 and 2001. Average perennial forb production at the Survey Area was approximately 2 percent, compazed to 9 percent and 6 percent in the Reference Area in 1999 and 2001, respectively. The Survey Area, however, had a higher amount of biennial forb production, which was attributed to the presence of yellow sweetclover (Melilotus o~cinalis). While sweet clover is considered valuable for forage, it was not included in the productivity estimates for perennial forbs. Wildlife species, including elk, have reportedly been observed grazing within the Survey Area. Domestic livestock have also been observed grazing within the Survey Area, including during the 2001 survey. A comparison of data from transects located in azeas that are heavily grazed by . livestock compared to other azeas not subjected to heavy grazing indicates that grazing does not RevegttationSurveyR<port-RPr(626)RevLdoUSeptttnber 6, 2001 t~