|
� r
<br /> 8 SOIL SURVEY
<br /> filter the leachate. Sewage lagoons require sealing. 60 percent of the unit. Aquents, which have a lighter
<br /> Lawns, shrubs, and trees grow well. Capability subclass colored surface layer, make up about 35 percent. About 5
<br /> Its irrigated. percent is Aquepts and Bankard sandy loam.
<br /> a2 Altvan loam, 1 to 3 percent slopes. This is a deep, These are deep, poorly drained soils that formed in
<br /> well drained soil on terraces at elevations of 4,500 to 4,900 recent alluvium. No one pedon is typical. Commonly the
<br /> feet. It formed in old alluvium deposited by the major soils have a mottled, mildly alkaline to moderately al-
<br /> rivers. Included in mapping are small areas of soils that kaline loamy or clayey surface layer and underlying
<br /> show evidence of poor drainage. Also included are small, material and are underlain by sand or sand and gravel
<br /> long and narrow areas of sand and gravel deposits. within 48 inches. In places they have a gleyed layer in the
<br /> Typically the surface layer of this Altvan soil is grayish underlying material.
<br /> brown loam about 10 inches thick. The subsoil is brown Most of the acreage is subject to flooding. The water
<br /> and light yellowish brown clay loam and sandy clay loam table is at or near the surface early in spring and recedes
<br /> about 14 inches thick. The substratum is calcareous loamy to as deep as 48 inches late in fall in some years.
<br /> sand about 5 inches thick over gravelly sand. These soils are used for rangeland and wildlife habitat.
<br /> Permeability and available water capacity are Some small areas have been reclaimed by major drainage
<br /> moderate. The effective rooting depth is 20 to 40 inches. and leveling and are used for irrigated crops.
<br /> Surface runoff is medium, and the erosion hazard is low. The potential native vegetation is dominated by alkali
<br /> This soil is used almost entirely for irrigated crops. It sacaton, switchgrass, and western wheatgrass. Saltgrass,
<br /> is suited to all crops commonly grown in the area, includ- sedge, rush, and alkali bluegrass are also prominent.
<br /> ing corn, sugar beets, beans, alfalfa, small grain, potatoes, Potential production ranges from 3,000 pounds per acre in
<br /> and onions. An example of a suitable cropping system is 3 favorable years to 2,000 pounds in unfavorable years. As
<br /> to 4 years of alfalfa followed by corn, corn for silage, range condition deteriorates, the switchgrass, alkali
<br /> sugar beets, small grain, or beans. Land leveling, ditch sacaton, and western wheatgrass decrease and saltgrass,
<br /> lining, and installing pipelines may be needed for proper sedge, and rush increase.
<br /> water application.
<br /> All methods of irrigation are suitable, but furrow ir- Management of vegetation should be based on taking
<br /> rigation is the most common. Barnyard manure and com- half and leaving half of the total annual production. Seed-
<br /> mercial fertilizer are needed for top yields. ing is difficult and costly because numerous tillage prac-
<br /> Windbreaks and environmental plantins of trees and tices are required to eliminate the saltgrass sod.
<br /> shrubs commonly grown in the area are generally well Switchgrass, western wheatgrass, alkali sacaton, tall
<br /> suited to this soil. Cultivation to control competing wheatgrass, and tall fescue are suitable for seeding. They
<br /> vegetation should be continued for as many years as can be seeded into a clean, firm seedbed. Seedbed
<br /> possible following planting. Trees that are best suited and preparation usually requires more than 1 year to
<br /> have good survival are Rocky Mountain juniper, eastern eliminate the saltgrass sod. A grass drill should be used.
<br /> redcedar, ponderosa pine, Siberian elm, Russian-olive, and Seeding early in spring has proven most successful.
<br /> hackberry. The shrubs best suited are skunkbush sumac, Wetland wildlife, especially waterfowl, utilize this unit.
<br /> lilac, Siberian neashrub, and American plum. The wetland plants provide nesting and protective cover,
<br /> This soil can produce habitat elements that are highly as well as some food. The nearby irrigated cropland,
<br /> suitable for openland wildlife including pheasant, cotton- where wildlife obtain much of their food and fmd protec-
<br /> tail, and mourning dove. Such crops as wheat, corn, and tive cover, makes this unit valuable to both wetland and
<br /> alfalfa provide suitable habitat for openland wildlife, openland wildlife.
<br /> especially pheasant. Tree and shrub plantings and Openland wildlife, especially pheasant, use this unit for
<br /> undisturbed nesting cover would enhance openland wil- cover and nesting. Deer find excellent cover in some
<br /> dlife populations. areas.
<br /> This Altvan soil has fair to good potential for urban These valuable wildlife areas should be protected from
<br /> and recreational development. The chief limiting soil fea- fire and fenced to prevent encroachment and overuse by
<br /> tures for urban development are the shrink-swell poten- livestock. They should not be drained.
<br /> tial of the subsoil as it wets and dries and the rapid These soils have good potential as a source of sand and
<br /> permeability of the sand and gravel substratum. Septic gravel. Capability subclass Vlw; Salt Meadow range site.
<br /> tank absorption fields function properly, but in places the 4—Aquolls and Aquepts, flooded. This nearly lever
<br /> substratum does not contain enough fines to properly map unit is in depressions in smooth plains and along the
<br /> filter the leachate. Sewage lagoons require sealing. bottoms of natural drainageways throughout the survey
<br /> Lawns, shrubs, and trees grow well. Capability subclass area. Aquolls, which have a dark colored surface layer
<br /> Ile irrigated. make up about 55 percent of the unit. Aquepts, whict
<br /> CTAquolls and Aquents, gravelly substratum. This have a lighter colored surface layer, make up about 2.`
<br /> nearly level map unit is on bottom lands and flood plains percent. About 20 percent is soils that are well drainer
<br /> of all the major streams in the survey area. Aquolls, and soils that have sandstone or shale within 48 inches o
<br /> which have a dark colored surface layer, make up about the surface.
<br />
|