Actions that do not address the questions of where and when, as well as what and why, may yield disappointing results. Glaciation resulted in a collage of landscape features. Viewed from close up, even these features are highly heterogeneous. For example, the Missouri Coteau, a large morainal belt, contains various types of moraines, glacial outwash plains, and small lake beds, each possessing different topography, soil types, and vegetation. Temporally, the climate of the Prairie Pothole Region is characterized by instability and extremes.
Droughts recur frequently and cause cyclic changes in the flora and fauna of the region.
Plant communities of the region, especially those in wetlands, have always been unstable. Cyclic weather patterns, grazing by huge herds of bison and other ungulates, and fires were integral to the landscape. Settlement of the region by Europeans resulted in massive changes to the prairie landscape. Tillage of natural grasslands not only caused the loss of much of the original prairie but fragmented the remaining grassland into small blocks surrounded by cropland. Free-ranging bison were nearly extirpated from the region and replaced by cattle.