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Soil descriptions • • 1D -Anvik loam, 6 to 15 percent slopes. This is a deep, well drained, moderately sloping to strongly sloping soil on mountainous uplands. It formed in colluvium and glacial drift derived from a variety of rocks. The average annual precipitation is about 18 inches, the average annual air temperature is about 38 degrees F, and the frost-free season is 35 to 75 days. Small areas of Youga and Muggins soils and Youga thick surface soils are included in mapping. Also included are similar soils that have a 5 to 8 inch thick dark-colored surface layer. Typically, the surface layer is brown loam about 10 inches thick. The subsurface layer is bleached, pinkish gray loam about 5 inches thick. The subsoil is light yellowish brown cobbly clay loam about 33 inches thick. The substratum is light yellowish brown cobbly light clay loam to a depth of 60 inches or more. Permeability is moderate and the available water capacity is high. Surface runoff is medium. The hazard of wind erosion is slight, and the hazard of water erosion is moderate. Most of the acreage has a woodland overstory and an understory of grasses and fortis. Grazing by livestock is the major use, but this soil is also used for recreation and wildlife. A cold climate and a short growing season limit the production of introduced grasses and preclude the use of this soil for crops. Management of this Anvik soil for range should include a deferred grazing system and limited thinning of the more densely wooded areas. Grasses recommended for seeding are slender wheatgrass, mountain brome, Arizona fescue, and big bluegrass. The dominant native vegetation consists of quaking aspen, lodgepole pine, Douglas-fir, and the understory consists of Thurber fescue, bluegrass, brome, and wheatgrass. The total annual production averages about 3,000 pounds of air-dry forage per acre. This soil is not used for timber production; there is only a scattering of coniferous trees. Areas have limited use for quaking aspen but can be used as calving sites by ranchers with cattle. Thinned-out trees are used for firewood. Excessive slope is the most limiting soil property to be considered in the design of access roads and recreation homesite subdivisions. Snow removal becomes an increasingly greater problem as more homes are built. Slope stabilization is difficult even where homes are constructed on nearly level pads. Surface runoff, caused by snowmelt, increases the erosion hazard on cu[ and fill slopes. Seeding of vegetation minimizes the erosion hazard, but establishing a stand is difficult. Homes should be designed to utilize existing slope and keep foundation cuts to a minimum. Roads should be designed to keep out and fill slopes to a minimum and provide drainage outlets for excessive snowmelt. All- weatherasphalt surfaces are impractical unless provisions are made to offset frost action. Wildlife on this wooded soil includes mule deer, elk, blue grouse, snowshoe hare, mourning dove, and chipmunks. The natural migration of deer and elk herds has been disturbed in many areas now used for recreation homesite subdivisions. Capability subclass Vle. 8B -Handran gravelly loam, 0 to 3 percent slopes. This is a deep, well drained, nearly level soil on terraces. It formed in alluvial deposiu derived from a variety of racks. The average annual precipitation is about 15 inches, the average annual air temperature is about 37 degrees F, and the host-free season is 30 to 75 days. Elevation is 7,500 to 9,000 feet. Small areas of Quander soil and Cumulic Cryaquolls are included in mapping. Typically, the surface layer is brown gravelly loam about 6 inches thick. The next layer is brown gravelly sandy loam about 9 inches thick. The underlying material is brown very cobbly sandy foam to a depth of 60 inches or more. Permeability is rapid, and the available water capacity is medium. Surface runoff is slow. The hazard of wind and water erosion is slight. Most ofthe acreage is rangeland, but some areas are used for'urigated grass hay, recreation, and wildlife. A cold climate and a short growing season limit production and preclude use of this soil as cropland. Management of the Handran soils for range requires a deferred grazing system and limited bntsh control. Where they are irrigated, these soils need proper water management to prevent over-vrigation. Grasses recommended for seeding include westem wheatgrass, slender wheatgrass, mountain brome, Arizona fescue, big bluegrass, and bluebunch wheatgrass. The dominant native vegetation consists of westem wheatgrass, fescue, serviceberry, antelope bitterbmsh, and big sagebmsh. The total annual production averages about 1,500 pounds of a'tr-dry forage per acre. Excessive amounts of small and large stones and rapid permeability are the most limiting soil properties to be considered in the design of access roads, septic systems, and recreation homesite subdivisions (fig. I). Stones in the soil profile interfere with excavations and cuts and fills. Leach fields should be designed carefully to eliminate the hazard of ground water pollution. All-weather asphalt surfaces are impractical unless provisions are made to offset frost action. Rangeland wildlife includes mule deer, sage grouse, white-tailed jackrabbit, coyote, mourning dove, ground squirrel, and yellow-bellied marmot. Capability subclass Vlls.