Texture is typically stratified layers of sand, coarse sand, or the gravelly, very gravelly, or extremely gravelly analogs or has strata of gravel. In some pedons it is sand. There are no competing series. Related soils are the Bixby and Fox series. Bixby and Fox soils do not have free carbonates within a depth of 20 inches.
Casco soils are on outwash plains, outwash terraces, eskers, kames, and moraines.
Slope gradients range from 0 to 70 percent. Casco soils formed in a thin layer of loamy alluvium underlain by calcareous stratified sandy outwash. Mean annual precipitation ranges from 28 to 40 inches. The frost free period ranges from about 135 to 200 days. Elevation ranges from 340 to 1500 feet.