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16— Cushman -Kutch complex, 8 to 25 percent slopes. These moderately deep, well drained, moderate- ly sloping to moderately steep soils are on upland' hills, ridges, and side slopes. Elevation ranges from about 5.300 to 6.400 feet. Average annual precipitation ranges from about 14 to 17 inches, average annual air tempera- ture is about 47 degrees F, and average frost -free period is about 135 days. The Cushman soil makes up about 50 percent of this -unit and the Kutch soil about.30 percent. Included with this complex in mapping, and making up about 20 percent of the unit, are Ascalon sandy loam, 4 to 8 percent slopes; Renohill- Louviers complex. 8 to 25 percent slopes; sandy soils that are similar to the Terry soils mapped in El Paso County; and sandstone outcrops {fig. 5). • . The Cushman soil formed in calcareous material weathered from interbedded shale and sandstone. Typi- cally, the surface layer is pale brown loam about 4 inches thick. The subsoil is grayish brown clay loam to a depth of about 20 inches. The substratum is light brown- ish gray silty clay to a depth of about 34 inches. Below that is olive interbedded shale and sandstone. • Permeability is moderate, and available water capacity is low to moderate. The effective rooting depth is 20 to ' 40 inches. Surface runoff is medium,• and the hazard of erosion is moderate to high. Deep gullies have formed along some drainageways and stock trails. •. The Kutch soils formed in fine textured calcareous • material weathered from clay shale. Typically, the gut -" face layer is grayish brown clay loam about 4 inches • thick. The subsoil Is grayish brown and light olive brown clay to a depth of about 22 inches. It is calcareous in the lower part. The substratum 'is grayish brown clay to a depth of about 30 inches. Below that is gray and olive shale. Permeability is stow, and available water capacity is moderate. The effective rooting depth is 20 to 40 inches. Surface runoff is medium to rapid, and the hazard of erosion is moderate. Some gullying has taken place in narrow drainageways. These soils are used mainly for grazing. They have poor potential for cropland and for windbreaks and envi- ronmental plantings. The Cushman soil has fair to poor 'pCtential for most engineering uses, and the Kutch soil. has poor potential. Rangeland vegetation on the Cushman soil is mainly blue grams, needlegrasses, prairie junegrass, sideoats grams, and western wheatgrass. When range condition deteriorates, grasses such. as blue grama and native bluegrasses increase. Sleepygrass and annuals replace' these grasses in a seriously deteriorated range. Seeding the range is recommended to revegetate de- pleted areas in order to protect the soil from wind and water erosion. Seeding to native grasses is desirable, but the range may also be seeded with tame species of _ grasses, such as Nordan crested wheatgrass, Russian wildrye, pubescent wheatgrass, or intermediate wheat - grass. Rangeland vegetation on the Kutch soil consists of western wheatgrass, blue grama, green needfegrass. s+- decals grama, and sedge. Contour furrowing or pitting aids in the recovery of depleted vegetation on this soil by reducing runoff and increasing water infiltration. Areas that have dense stands of pricklypear or rabbitbrush can be managed bf_shemicaf control_ . • These soils are generally not suited to windbreaks or environmental plantings. Onsite investigation is needed to determine which special planting practices are needed to insure survival. The main limiting soil features of these soils, where they are used for homesites or other urban uses, are the presence of sandstone and shale at a depth of 20 to 40 inches, shrink -swell potential, slow permeability, and steep slopes. Intensive and costly measures are needed to offset these limitations. • This complex is in capability subclass Vle,.nonirrigated. NEL CLASS I FOR TJIND AND WATER . POSSIBLE HYDRIC INCLUSIONS IN SWALES MEETING PONDING CRITE,RLA.