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<br />The possibility of settlement can be minimized by
<br />compacting the building site before construction is
<br />begun. If buildings are constructed on this unit, properly
<br />designing foundations and footings and diverting runoff
<br />away from buildings help to prevent structural damage
<br />because of shrinking and swelling. Access roads should
<br />be designed to provide adequate cut slope grade, and
<br />drains are needed to control surface runoff and keep sail
<br />losses to a minimum.
<br />This map unit is in capability subclass IVe. It is in
<br />Rolling Loam range site.
<br />34-Forelle loam, 8 to 15 percent slopes. This
<br />deep, well drained soil is on tenaces and uplands. It
<br />formed in eolian and alluvial material derived dominantly
<br />from sedimentary rock. Areas are elongated and are 20
<br />to 250 acres. The native vegetation is mainly low shrubs
<br />and grasses. Elevation is 5,600 to 7,200 feet. The
<br />average annual precipitation is 15 to 18 inches, the
<br />average annual air temperature is 42 to 45 degrees F,
<br />and the average frost-free period is 80 to 105 days.
<br />Typically, the surface layer is pale brown loam 4
<br />inches thick. The upper 12 inches of the subsoil is
<br />yellowish brown clay loam, and the lower 5 inches is
<br />light yellowish brown loam. The substratum to a depth of
<br />60 inches or more is very pale brown loam.
<br />Included in this unit are small areas of Dollard silty
<br />clay loam, Patent loam, Work loam, and Zoltay clay
<br />loam. Included areas make up about 15 percent of the
<br />total acreage. The percentage varies from one area to
<br />another.
<br />Permeability of this Forelle soil is moderate. Available
<br />water capacity is high. Effective rooting depth is 60
<br />inches or more. Runoff is medium, and the hazard of
<br />water erosion is moderate to high.
<br />This unit is used for nonirrigated crops, livestock
<br />grazing, and wildlife habitat.
<br />If this unit is used for nonirrigated crops, the main
<br />limitations are the hazard of erosion, a short growing
<br />season, and low precipitation. Wheat is the main
<br />nonirrigated crop. Because precipitation Is not sufficient
<br />for annual cropping, a cropping system that includes
<br />small grain and summer fallow is most suitable.
<br />Maintaining crop residue on or near the surface
<br />reduces runoff, reduces soil blowing, and helps to
<br />maintain soil filth and organic matter content. Soil
<br />blowing can also be controlled by keeping the soil rough
<br />and cloddy when it is not protected by vegetation. On
<br />long slopes, chiseling the stubble in fall slows runoff and
<br />reduces soil loss in years when the snow melts rapidly
<br />while the soil is still frozen. Chiseling also promotes
<br />better aeration. The more steeply sloping areas are
<br />poorly suited to cultivation.
<br />The potential plant community on this unit is mainly
<br />western wheatgrass, prairie junegrass, big sagebrush,
<br />Douglas rabbitbrush, streambank wheatgrass, antl
<br />needleandthread. The production of forage is limited by
<br />• Soil survey
<br />a short growing season and low precipitation. The
<br />average annual production of air-dry vegetation is about
<br />750 pounds per acre.
<br />If the range is overgrazed, the proportion of preferred
<br />forage plants decreases and the proportion of less
<br />preferred forage plants increases. Therefore, livestock
<br />grazing should be managed so that the desired balance
<br />of preferred species is maintained in the plant
<br />community.
<br />Management practices suitable for use on this unit are
<br />proper range use, deferred grazing, rotation grazing, and
<br />brush management. If the range is in poor condition,
<br />seeding is also a suitable practice where slopes are less
<br />than 15 percent. For successful seeding, prepare a
<br />seedbed and drill in the seed. The plants selected for
<br />seeding should meet the seasonal requirements of
<br />livestock or wildlife, or both.
<br />If this unit is used for urban development, the main
<br />limitations are the potential for shrinking and swelling,
<br />the hazard of frost action, and slope.
<br />This map unit is in capability subclass IVe,
<br />nonirrigated. It is in Rolling Loam range site.
<br />35-Gaynor-Mldwey silty clay looms, dry, 2 to 25
<br />percent slopes. This map unit is on tow hills, ridges,
<br />and knolls. Areas are irregular in shape and are 200 to
<br />7,000 acres in size. The native vegetation is mainly salt-
<br />tolerant desert shrubs and grasses. Elevation is 5,200 tc:
<br />5,800 feet. The average annual precipitation is 10 to 13
<br />inches, the average annual air temperature is 46 to 50
<br />degrees F, and the average frost-free period is 105 to
<br />130 days.
<br />This unit is 50 percent Gaynor silty clay loam that ha:
<br />slopes of 2 to 15 percent and 35 percent Midway silty
<br />clay loam that has slopes of 2 to 25 percent. The
<br />Gaynor soil is on ridges, and the Midway soil is on the
<br />steeper side slopes and on the crests of knolls. The
<br />components of this unit are so intricately intermingled
<br />that it was not practical to map them separately at the
<br />scale used.
<br />Included in this unit are small areas of Gtenton sandy
<br />loam, Killpack silty clay loam, and Walknolls channery
<br />sandy loam. The Walknolls soil is on benches. Included
<br />areas make up about 15 percent of the total acreage.
<br />The percentage varies from one area to another.
<br />The Gaynor soil is moderately deep and well drained.
<br />It formed in calcareous residuum derived from shale.
<br />Typically, the upper part of the surface layer is pale
<br />brown silty clay loam about 2 inches thick, and the lowc~
<br />part is very pale brown silty clay about 6 inches thick.
<br />The next layer is pale brown silty clay 13 inches thick.
<br />The underlying material is light yellowish brown silty cla;
<br />that has some gypsum crystals and is 8 inches thick.
<br />Shale is at a depth of 29 inches. Depth to shale ranger
<br />from 20 to 40 inches. The soil has cracks as much as 1
<br />1 /2 inches wide and 20 inches deep when dry. It is
<br />calcareous throughout.
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