The Darien series consists of very deep, somewhat poorly drained soils formed in Wisconsinan age till on till plains and moraines.
Permeability is moderately slow in the subsoil and slow in the substratum.
Slope ranges from 0 to 25 percent. Mean annual temperature is about 49 degrees F, and mean annual precipitation is about 36 inches. Darien silt loam, on a 3 percent slope in a cultivated field. Solum thickness ranges from 30 to 50 inches. Depth to carbonates ranges from 25 to 48 inches.