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EXHIBIT I 68-Ustic Torriorthents, moderately steep. These are deep, excessively drained soils on terrace breaks and escarpments at elevations of 4,450 to 5,100 feet They formed in gravelly alluvium and have slopes of 9 to 25 percent. Included in mapping are small areas of soils that have pockets of sandy loam and loam in the underlying material. Typically the surface layer is pale brown gravelly sand about 10 inches thick. The underlying material to a depth of 60 inches is pale brown gravelly sand. Permeability is rapid. Available water capacity is low. The effective rooting depth is 60 inches or more. Surface runoff is medium, and the erosion hazard is moderate. The potential native vegetation is dominated by little bluestem, sideoats grams, sand reedgrass, blue grams, hairy grams, switchgrass, and needleandthread. Potential production ranges from 700 pounds per acre in favorable years to 200 pounds in unfavorable years. As range condi- tion deteriorates, the tali and mid grasses decrease, blue grams and hairy grams increase, and forage production drops. Management of vegetation should be based on taking half or less of the total annual production. Deferred graz- ing is practical in improving range condition. Seeding and mechanical treatment are impractical. Windbreaks and endu•onmental plantings generally are not suited to these soils. Onsite investigation is needed to determine if plantings aze feasible. Wildlife populations_aze limited because the necessary habitat elements aze lacking. Because most of the acreage is rangeland, only rangeland wildlife, for example sealed quail and antelope, are typical. Extreme care is needed in managing livestock grazing in order to provide suitable :habitat on these soils. Potential is poor for urban and recreational develop- ment. The chief limiting soil features are the loose, coazse textured soil, steep slopes, and rapid permeability. Capa- bility subclass VIIs irrigated, VIIs nonirrigated; Gravel Breaks range site.