Land use: About 40 percent of this area is rangeland, and 40 percent is cropland. About 20 percent of the area is urban land, woodland, or pasture or is used for other purposes. Nearly all the area is in farms or ranches. Most cropland is in the north, but some is throughout the area. Winter wheat is the major cash crop. Alfalfa, cotton, grain sorghum, peanuts, and soybeans are important crops locally. The range and pasture are grazed mainly by beef cattle, but locally there are some dairy cattle. Soil erosion is a major concern of management if the soils are intensively cultivated or range and pasture are overgrazed.
Elevation and topography: Elevation ranges from 300 to 500 m, increasing gradually from east to west. On this dissected plain, the divides are undulating to gently rolling and the valley sides are hilly and steep. Flood plains of large streams are wide and level and are less dissected by stream channels than those to the west. Local relief is mainly in meters.
Climate: Average annual precipitation - 625 to 900 mm. Maximum precipitation is in spring and the minimum in winter. Annual snowfall ranges from 30 cm in the north to 10 cm in the south. Average annual temperature - 14 to 18 C. Average freeze-free period - 190 to 230 days.
Water: The moderate and somewhat erratic precipitation is the source of water for crops and pasture. Several large rivers that cross the area from west to east are potential sources of irrigation water but currently are little used for this purpose. Small ponds on individual farms provide flood control, recreation, irrigation water, or water for livestock. A few large ponds and reservoirs are a source of municipal water and are also used for recreation. In areas where the valleys have deep sand and gravel, shallow wells provide moderate quantities of water for domestic use and for livestock. Ground water is scarce and generally is highly mineralized in sloping areas where the underlying sandstone and shale are near the surface.
Soils: The major soils are Ustolls. They are loamy or clayey and have a thermic temperature regime, an ustic moisture regime, and mixed mineralogy. The nearly level to sloping, well drained or moderately well drained, deep or moderately deep Argiustolls (Anocon, Grant, Pond Creek, Tabler, Shellabarger, and Stoneburg series) and Paleustolls (Bethany, Kirkland, and Renfrow series) are on uplands. The nearly level to steep, well drained, shallow to deep Haplustolls (Minco, Nash, and Lucien series) are on uplands. The nearly level, well drained or moderately well drained, deep Haplustolls (Miller, Port, and Reinach series) are on flood plains and low terraces. Minor soils include deep Haplustalfs (Bluegrove, Grainola, Pratt, and Steedman series) on uplands and Ustifluvents (Gaddy, Clairemont, and Yahola series) and Udifluvents (Gracemont and Gracemore series) on flood plains.
Potential natural vegetation: This area supports mixed prairie vegetation. Woody trees and shrubs are in the major drainageways. Indiangrass, big bluestem, switchgrass, and little bluestem are dominant species on the deeper soils and in the valleys. Little bluestem usually is dominant on the uplands and on shallow soils.
(From "Land Resource Regions and Major Land Resource Areas of the United States". United States Department of Agriculture Soil Conservation Service Handbook 296. Dec. 1981. page 54.)