Northern Prairie Wildlife Research Center
|46c. Glacial Lake Basins||Level IV Ecoregion|
|The Northern Glaciated Plains
ecoregion is characterized by a flat to gently rolling landscape
composed of glacial drift. The subhumid conditions foster a grassland
transitional between the tall and shortgrass prairie. High concentrations
of temporary and seasonal wetlands create favorable conditions for duck
nesting and migration. Though the till soil is very fertile, agricultural
success is subject to annual climatic fluctuations.
The Glacial Lake Basins were once occupied by Lake Souris, Devils Lake, and Lake Dakota. These proglacial lakes were formed when major stream or river drainages were blocked by glacial ice during the Pleistocene. The smooth topography of the Glacial Lake Basins, even flatter than the surrounding drift plains (ecoregions 46g, 46i, and 46n), resulted from the slow buildup of water-laid sediments. The level, deep soils on the lake plains are intensively cultivated. In the north, the primary crops are spring wheat, other small grains, and sunflowers; in the Lake Dakota basin of South Dakota, corn and soybeans are more prevalent.
Area (square miles): 3584
Surficial Material and Bedrock
Order (Great Groups)
Precipitation - Mean annual (inches)
Potential Natural Vegetation
Western wheatgrass, needleandthread, blue grama, green needlegrass.
Land Use and Land Cover
Extensively tilled for durum and spring wheat, sunflowers, and flax. Corn and soybeans south.