The type of soil commonly found in the Interior Plains is Loamy soil.

Loamy soil is ideal for agriculture because it is a balanced mixture of sand, silt, and clay, offering good drainage while retaining moisture and nutrients. This makes the Interior Plains, particularly in regions like the U.S. Great Plains and Canada's Prairie Provinces, highly productive for farming. The rich, fertile loamy soil supports the growth of crops such as wheat, corn, and other grains, contributing to the region's reputation as one of the most important agricultural areas in North America.