Northern Prairie Wildlife Research Center
|43g. Semiarid Pierre Shale Plains||Level IV Ecoregion|
|Home||The Northwestern Great Plains
ecoregion encompasses the Missouri Plateau section of the Great
Plains. 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
West of the Cheyenne river, the Semiarid Pierre Shale Plains take on a drier aspect. Although the precipitation is only one or two inches less per year than in ecoregion 43f, successful yields for tilled crops occur more infrequently than they do further east. In this region the mixed-greass prairie has a predominance of shortgrass species, e.g., little bluestem and buffalograss.
Area (square miles): 3853
Surficial Material and Bedrock
Order (Great Groups)
Precipitation - Mean annual (inches)
Potential Natural Vegetation
Shortgrass prairie grasses such as western wheatgrass, green needlegrass, blue grama and buffalograss.
Land Use and Land Cover
Cattle grazing, rangeland. Dryland farming of winter wheat and alfalfa.