Mean annual temperature is about 51 degrees F. Mean annual precipitation is about 33 inches near the type location. These include the Andres , Elliott , Mokena , and Symerton soils. Andres soils are somewhat poorly drained. Elliott and Mokena soils have argillic horizons. Symerton soils are well or moderately well drained.
Surface runoff is slow or ponded.
Permeability is moderate in the overburden material and slow or very slow in the till or lake bed sediments. Most areas are drained and cropped to corn, soybeans, small grains, and meadow. Native vegetation was swamp grasses. The series is of moderate extent with an estimated acreage of 60,000. Kankakee County, Illinois, 1975.