Section 331E Northern Glaciated Plains
Geomorphology. This area includes gently undulating to rolling continental glacial till plains with areas of kettle holes, kames, and moraines. Slopes adjacent to major stream valleys are steep. Elevation ranges from 2,000 to 6,000 ft (610 to 1,830 m). This Section is within the Great Plains physiographic province.
Lithology and Stratigraphy. Glacial till is underlain by soft Cretaceous and Lower Tertiary non-marine sedimentary rocks.
Soil Taxa. Soils include predominantly frigid Borolls. These soils are generally deep and have loamy textures.
Potential Natural Vegetation. Kuchler mapped vegetation as wheatgrass-needlegrass. The natural prairie vegetation is characterized by western wheatgrass, needleandthread, green needlegrass, and blue grama. Little bluestem occurs on sloping and thin soils. Prairie cordgrass, northern reedgrass, and slim sedge occur on wet soils. Western snowberry and prairie rose are common shrubs.
Fauna. Birds are very similar to those that occur in Section 332A, but include some species associated with the Missouri River (Missouri Coteau region). These species are typical of riparian habitat, or typical of both prairie potholes and badlands. Several species follow the Missouri River upstream to near the western extent of their ranges; these include piping plover, least tern, chimney swift, eastern phoebe, purple martin, eastern bluebird, black-and-white warbler, ovenbird, indigo bunting, rose-breasted grosbeak, orchard oriole, and field and swamp sparrows. Western species reaching the edge of their range include lazuli bunting and black-headed grosbeak. Typical herbivores and carnivores include white-tailed deer, mule deer, pronghorn, and bobcat. Smaller common herbivores include the white-tailed jackrabbit, white-tailed prairie dog, and black-tailed prairie dog. Less common species associated with this Section includes black-tailed jackrabbit, swift fox, dwarf shrew, and hispid pocket mouse. The black-footed ferret and bison are species which are historically associated with this Section. Herpetofauna typical of this Section are the snapping turtle, spiney softshell turtle, smooth green snake, and the prairie rattlesnake.
Climate. Precipitation ranges from 10 to 20 in (250 to 510 mm) with more than half falling during the growing season. Winters are extremely cold with desiccating winds; precipitation is snow. Climate is cold continental, with warm, dry summers. Temperature averages 37 to 45 F (3 to 7 C). The growing season lasts 110 to 135 days.
Surface Water Characteristics. Low to medium density dendritic drainage patterns change to complex, high density dendritic patterns where the sedimentary rocks are exposed due to erosion of badlands.
Disturbance Regimes. Fire and drought are the principal natural sources of disturbance.
Land Use. Dryland farming and livestock grazing occur on most of the area.
