It is a semiarid rolling plain of shale, siltstone, and sandstone punctuated by occasional buttes and badlands. Native grasslands persist in areas of steep or broken topography, but they have been largely replaced by spring wheat and alfalfa over most of the ecoregion. Agriculture is limited by erratic precipitation patterns and limited opportunities for irrigation. T he Dense Clay Prairie differs from the surrounding ecoregions in its lack of vegetative cover. Only the tall grasses show thinly against the dark-colored clay.
Riparian woodland is absent from draws and stream corridors.
This fragile landscape must be managed carefully to avoid erosion and blowing soil. Sheep farming is the major land use. Geology Surficial Material and Bedrock Cretaceous Pierre shale. Land Use and Land Cover Sheep and cattle ranching. Fragile grassland cover.