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desirable understory range plants. These areas have not been converted to more intensive <br />land uses because of topographic restrictions affecting irrigation water application and the <br />occurrence of rock outcrops or shallow soils. The type usually occurs where slopes are too <br />steep to irrigate or where it was not feasible to bring water to the land via a ditch. This <br />sagebrush type was delineated based on the dominance of sagebrush within these areas. The <br />sage brush ranged in height from 1 ft. to 2.5 ft. with a average sagebrush height of 1.5 ft. <br />Sagebrush vigor and form are restricted by shallow depth to bedrock in this type. Slopes <br />ranged 3 to 60 percent. Some areas mapped as such may occasionally receive supplemental <br />moisture during the growing season from adjacent agricultural activities, however, a sagebrush <br />overstory with an associated understory of introduced and native species are present along <br />with the irrigated pasture invader species Kentucky bluegrass. <br />Total vegetation cover (first hit) for the type averaged 34 percent, with bare ground at 36 <br />percent, litter at 22 percent, and bedrock or rock fragments at 8 percent (Table 2.04.10 -21). <br />Lichen and moss accounted for 1.1 percent of the mean cover. The shrub component <br />dominated with 16.2 percent cover followed closely by the perennial grass component at 7.5 <br />percent cover. Annual grasses at 6.8 percent cover, followed in importance. Consistent with <br />the type designation, sagebrush ( Artemisia tridentata had the highest perennial species cover <br />at 13.9 percent (47 percent frequency), while the ubiquitous invader of sagebrush rangelands, <br />cheatgrass ( Anisantha tectorum had a cover of 6.8 percent (41 percent frequency). Blue <br />grama had the third highest cover at 5.1 percent (29 percent frequency). The remaining <br />species generally contributed less than one percent cover to the mean total vegetative cover. <br />Total herbaceous production (including shrubs) totaled 43.01 g /m2 or 386.02 pounds /acre <br />(Table 2.04.10 -22). Herbaceous production without the shrub component totaled 8.07g/m2 or <br />74.1 pounds /acre. The perennial shrub component contributed the highest value at 34.94 g/m <br />(311.4 pounds /acre) followed by perennial grasses at 5.47 g /m (48.8 pounds /acre). While the <br />contribution of annual grasses and forbs was (2.6 and 0.2 g /m , respectively), their actual <br />contribution to annual production is most likely higher. In order to sample the perennial <br />species at the peak of their production, many of the earlier maturing annual species were <br />senescent or were already gone from the stand. <br />Revised September 2010 (PR 06) 2.04.10 -71 <br />