The mean annual temperature is about 48 to 53 degrees F., mean annual precipitation ranges from 30 to 42 inches, frost free days range from 130 to 180 days, and elevation ranges from 580 feet to 1530 feet above sea level. The moderately well drained Miami and well drained Riddles soils are on knolls of till plains and on narrow summits and backslopes of dissected till plains. The moderately well drained Wakarusa and Williamstown soils are on knolls on till plains and on narrow summits and backslopes on dissected till plains. The somewhat poorly drained Crosby and Crosier soils are on swells on till plains and moraines. Brookston soils are poorly drained.
Surface runoff is negligible to low.
Permeability is moderate in the subsoil and moderately slow in the underlying material. An intermittent apparent high water table is 0.5 foot above the surface to 1 foot below the surface in most years. Most areas are used to grow corn, soybeans, oats, wheat, and hay. Small areas are in permanent pasture or woodlots. Native vegetation is deciduous forest, marsh grasses, and sedges.