Caddo soils are less clayey and are grayer throughout. Susquehanna soils have fine textured upper B horizons. Somewhat poorly drained. Runoff is slow to very slow, internal drainage is slow, and permeability is very slow. Mostly in forest but a few areas are in pasture.
Trees are dominantly post oak and other oaks, sweetgum, hickory, and holly.
Trees on the mounds are mainly shortleaf and loblolly pines. The western part of the southern Coastal Plain in Louisiana, Arkansas, Texas, and possibly Alabama and Mississippi. The series is of moderate extent. This soil was formerly classified as a Planosol.