Irondale soils are in residuum from igneous rocks, are 20 to 40 inches to bedrock, and have dominantly cobbly textures. Lew soils have friable B horizons and fragments of greenstone. Mertz soils have angular rock fragments of chert and sandstone. Pattenburg soils have sola less than 40 inches thick and friable B horizons. Weverton soils are in slope creep materials over residuum and are confined to the Blue Ridge Anticlinorium.
Croom soils are on dissected uplands of the northern Atlantic Coastal Plain.
They are on dissected convex slopes, hillsides, and hilltops. Slopes range from 0 to 40 percent. They formed in gravelly, sandy and clayey fluvial deposits and deltaic deposits. The mean annual temperature is 50 to 58 degrees F., and mean annual precipitation is 38 to 44 inches. These are the Aura , Chillum , Sassafras and Beltsville soils.