Researchers evaluated and refined a low-input cropping system at DeSoto National Wildlife Refuge near Missouri Valley, Iowa. DeSoto is located within the Missouri River floodplain in Harrison and Pottawattamie Counties in Iowa and in Washington County in Nebraska. The nearly level area includes cropland, grassland, timber, marshes, and DeSoto Lake, into which three drainage ditches empty runoff. The majority of the drained acres is managed by farmers for row-crop production, primarily in corn and soybeans planted in two-year rotations.