Mexico soils have at least one subhorizon in the argillic horizon that contains more than 52 percent clay . Clarksdale soils are on summits and side slopes on loess-mantled ground moraines. Slope gradients commonly are 0 to 2 percent but range to 7 percent. Clarksdale soils formed in loess. They are in areas on uplands between Typic Hapludalfs on crests and side slopes near drainageways and Argiudolls on ground moraines farther from the drainageways.
Climate is midcontinental with hot summers and cold winters.
These are the Downs , Ipava , Keomah , Rozetta , Rushville , and Sable soils. The moderately well drained Downs and Rozetta soils are in similar and more sloping areas. Ipava and Keomah soils are on similar nearby landscapes and form a biosequence with Clarksdale soils. The poorly drained Rushville soils do not have a dark surface layer and are on nearly level or slightly depressional areas. The poorly drained Sable soils have mollic epipedons and are typically on broad upland areas farther from the dissecting drainageways than Clarksdale soils.