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EXHIBIT I 3-Aquolls and Aquents, gravelly substratum. This nearly level map unit is on bottom lands and flood plains of all the major streams in the survey area. Aquolls, which have a dark colored surface layer, make up about 60 percent of the unit. Aquents, which have a lighter colored surface layer, make up about 35 percent. About 5 percent is Aquepts and Bankard sandy loam. These are deep, poorly drained soils that formed in recent alluvium. No one pedon is typical. Commonly the soils have a mottled, mildly alkaline to moderately al- kaline loamy or clayey surface layer and underlying material and are underlain by sand or sand and gravel within 48 inches. In places they have a gleyed layer in the underlying material. Most of the acreage is subject to flooding. The water table is at or near the surface early in spring and recedes to as deep as 48 inches late in fall in some years. These soils are used for rangeland and wildlife habitat. Some small areas have been reclaimed by major drainage and leveling and are used for irrigated crops. The potential native vegetation is dominated by alkali sacaton, switchgrass, and western wheatgrass. Saltgrass, sedge, rush, and alkali bluegrass are~•.also prominent. Potential production ranges from 3,000 pounds per acre in favorable years to 2,000 pounds in unfavorable years. As range condition deteriorates, the switchgrass, alkali sacaton, and western wheatgrass decrease and saltgrass, sedge, and rush increase. Management of vegetation should be based on taking half and leaving half of the total annual production. Seed- ing is difficult and costly because numerous tillage prac- tices aze required to eliminate the saltgrass sod. Switchgrass, western wheatgrass, alkali sacaton, tall wheatgrass, and tall fescue are suitable for seeding. They can be seeded into a clean, fun seedbed. Seedbed preparation usually requires more than 1 year to eliminate the saltgrass sod. A grass drill should be used. Seeding early in spring has proven most successful. Wetland wildlife, especially waterfowl, utilize this unit. The wetland plants provide nesting and protective cover, as well as some food. The nearby irrigated cropland, where wildlife obtain much of their food and find protec- tive cover, makes this unit valuable to both wetland and openland wildlife. Openland wildlife, especially pheasant, use this unit for cover and nesting. Deer find excellent cover in some areas. These valuable wildlife areas should be protected from fire and fenced to prevent encroachment and overuse by livestock. They should not be drained. These soils have good potential as a source of sand and gravel. Capability subclass VIw; Salt Meadow range site. 10-Bankard sandy loam, 0 to 3 percent elopes. This is a deep, somewhat excessively drained soil on flood plains at elevations of 4,950 to 5,000 feet. It formed in stratified recent alluvium along streams and rivers. In- cluded in mapping are numerous sand and gravel bars and small areas of noncalcareous soils. Typically the surface layer of this Bankazd soil is brown sandy loam about 4 inches thick. The underlying material to a depth of 60 inches is pale brown calcareous sand stratified with thin lenses of sandy loam, loam, and fine gravel. Permeability is moderately rapid. Available water capacity is low. The effective rooting depth is 60 inches or more. Surface runoff is slow, and the erosion hazard is~ low. This soil is suited to limited cropping. It is sandy and subject to flooding. Pasture is the best use. Tall wheat- grass, tall fescue, and annual sweetclover are some of the . most suitable crops. Light, frequent irrigation by furrows and flooding is best. Commercial fertilizer improves the ,amount and value of forage produced. The potential native vegetation is dominated by switchgrass, indiangrass, sand bluestem, sand reedgrass, ~sideoats grams, needleandthread, and blue grams. Much of this range site includes other soils and vegetation in such a complex pattern that it is difficult to map them separately. Potential production ranges from 2,500 pounds per acre in favorable years to 1,500 pounds in unfavorable years. As range condition deteriorates, the tall and mid grasses decrease; blue grams, sand dropseed, and forbs increase; and forage production drops. Undesirable weeds and annuals invade the site as range condition becomes poorer. Management of vegetation should be based on taking half and leaving half of the total annual production. Seed- ing is desirable only in areas large enough to interseed or to prepare a seedbed. Switchgrass, sand bluestem, sand reedgrass, sideoats grams, little bluestem, blue grams, pu- bescent wheatgrass, and intermediate wheatgrass are suitable for seeding. This soil can be seeded by using an interseeder or a firm, clean sorghum stubble. A grass drill is required. Seeding early in spring has proven most suc- cessful. This soil is generally not suited to the establishment and growth of trees and shrubs. Onsite investigation is needed to determine feasibility and possible tree and _ shrub species. Wildlife is an important secondary use of this soil. The cropland areas provide favorable habitat for ring-necked pheasant and mourning dove. Many nongame species can be attracted by establishing areas for nesting and escape cover. For pheasants, undisturbed nesting cover is essen- tial and should be included in plans for habitat develop- ment, especially in areas of intensive agriculture. Range- land wildlife, for example, deer and antelope, can be at- tracted by managing livestock grazing and reseeding where needed. This soil is not suited to urban or recreational develop- . ment because of the flood hazard. Capability subclass IVw irrigated, VIw nonirrigated; Sandy Bottom land range site.