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<br />6.4.9 Exhibit 1 -Soils Information
<br />SOIL SURVEY
<br />40-Nunn loam, 1 to 3 percent slopes. This is a deep,
<br />well drained soil on terraces at elevations of 4,550 to 5,000
<br />feet. [t formed in mixed alluvium. Included in mapping
<br />are small, long and narrow areas of sand and gravel
<br />deposits and small areas of soils that are subject to occa-
<br />sional flooding. Some leveled areas are also included.
<br />Typically the surface layer of this Nunn soil is grayish
<br />brown loam about 12 inches thick. The subsoil is light
<br />brownish gray clay loam about 12 inches thick. The upper
<br />part of the substratum is light brownish gray clay loam.
<br />The lower part to a depth of 60 inches is brown sandy
<br />loam.
<br />Permeability is moderately ~ slow. Available water
<br />capacity is high. The effective rooting depth is 60 inches
<br />or more. Surface runoff is medium, and the erosion
<br />hazard is low.
<br />In irrigated areas this soil is suited to all crops com-
<br />monly grown in the area, including corn, sugar beets,
<br />beans, alfalfa, small grain, potatoes, and onions. An exam-
<br />ple of a suitable cropping system is 3 to 9 years of alfalfa
<br />followed by corn, corn for silage, sugar beets, small grain,
<br />or beans. Generally such characteristics as a high clay
<br />content or a rapidly permeable substratum slightly
<br />restrict some crops.
<br />All methods of imgation are suitable, but furrow ir-
<br />rigation is the most common. Proper irrigation water
<br />management is essential. Barnyard manure and commer-
<br />cial fertilizer are needed for top yields.
<br />Most nonirrigated areas are used for small grain. The
<br />soil is summer fallowed in alternate years. Winter wheat
<br />is the principal crop. If the crop is winterkilled, spring
<br />wheat can be seeded. Generally precipitation is too low
<br />for beneficial use of fertilizer.
<br />Such practices as stubble mulch farming, stripcropping,
<br />and minimum tillage are needed to control soil blowing
<br />and water erosion.
<br />The potential native vegetation is dominated by blue
<br />grama. Several mid grasses, such as western wheatgrass
<br />and needleandthread, are also present. Potential produc-
<br />tion ranges from 1,600 pounds per acre in favorable years
<br />to 1,000 pounds in unfavorable years. As range condition
<br />deteriorates, the mid grasses decrease; blue grama, buf-
<br />falograss, snakeweed, yucca, and fringed sage increase;
<br />and forage production drops. Undesirable weeds and an-
<br />nuals invade the site as range condition becomes poorer.
<br />Management of vegetation on this soil should be based
<br />on taking half and leaving half of the total annual produc-
<br />tion. Seeding is desirable if the range is in poor condition.
<br />Sideoa[s grama, little bluestem, western wheatgrass, blue
<br />grama, pubescent wheatgrass, and crested wheatgrass are
<br />suitable for seeding. The grass selected should meet the
<br />seasonal requirements of livestock. It can be seeded into
<br />a clean, firm sorghum stubble, or it can be drilled into a
<br />firm prepared seedbed. Seeding early in spring has
<br />proven most successful.
<br />Windbreaks and environmental plantings of trees and
<br />shrubs commonly grown in the area are generally w•el]
<br />suited to this soil. Cultivation to control competing
<br />vegetation should be continued for as many years as
<br />possible following planting. Trees that are best suited and
<br />have good survival are Rocky Mountain juniper, eastern
<br />redcedar, ponderosa pine, Siberian elm, Russian-olive, and
<br />hackberry. The shrubs best suited are skunkbush sumac,
<br />lilac, Siberian peashrub, and American plum.
<br />Wildlife is an important secondary use of this soil. The
<br />cropland areas provide favorable habitat for ring-necked
<br />pheasant and mourning dove. Many nongame species can
<br />be attracted by establishing areas for nesting and escape
<br />cover. For pheasants, undisturbed nesting cover is essen-
<br />tial and should be included in plans for habitat develop-
<br />ment, especially in areas of intensive agriculture. Range-
<br />land wildlife, for example, the pronghorn antelope, can be
<br />attracted by developing livestock watering facilities,
<br />managing livestock grazing, and reseeding where needed.
<br />This soil has fair to poor potential for urban develop-
<br />ment. It has moderate to high shrink swell, low strength,
<br />and moderately slow permeability. These features create
<br />problems in dwelling and road construction. Those areas
<br />that have loam or sandy loam in the lower part of the
<br />substratum are suitable for septic tank absorption fields
<br />and foundations. Some areas of this soil are adjacent to
<br />streams and are subject to occasional flooding. The poten-
<br />tial is fair for such recreational development as camp and
<br />picnic areas and playgrounds. Capability subclass IIe ir-
<br />rigated, IIIc nonirrigated; Loamy Plains range site.
<br />41-Nunn clay loam, 6 to 1 percent slopes. This is a
<br />deep, well drained soil on terraces and smooth plains at
<br />elevations of 4,550 to 5,150 feet. It formed in mixed allu-
<br />vium and eolian deposits. Included in mapping are small,
<br />long and narrow areas of sand and grave] deposits and
<br />small areas of soils that are subject to occasional flooding.
<br />Some small leveled areas are also included.
<br />Typically the surface layer of this Nunn soil is grayish
<br />brown clay loam about 9 inches thick. The subsoil is light
<br />brownish gray clay loam about 14 inches thick. The upper
<br />part of the substratum is clay loam. The lower part to a
<br />depth of 60 inches is sandy loam.
<br />Permeability is moderately slow. Available water
<br />capacity is high. The effective rooting depth is 60 inches
<br />or more. Surface runoff is slow, and the erosion hazard is
<br />low.
<br />This soil is used almost entirely for imgated crops. It
<br />is suited to all crops commonly grown in the area, includ-
<br />ing corn, sugar beets, beans, alfalfa, small grain, potatoes,
<br />and onions. An example of a suitable cropping system is 3
<br />to 4 years of alfalfa followed by corn, corn for silage,
<br />sugar beets, small grain, or beans. Few conservation prac-
<br />tices are needed to maintain top yields.
<br />All methods of irrigation are suitable, but furrow ir-
<br />rigation is the most common. Barnyard manure and com-
<br />mercial fertilizer are needed for top yields.
<br />Windbreaks and environmental plantings of trees and
<br />shrubs commonly grown in the area are generally well
<br />suited to this soil. Cultivation to control competing
<br />vegetation should be continued for as many years as
<br />possible following planting. Trees that are best suited and
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