The soils involved in the eastern coastal-plain states were of the Tifton, Bladen, Orangeburg, Portsmouth, Norfolk, and Sassafras series. These belong to the podzolic group, including both the red-yellow and the gray-brown zones. They have all been developed from coastal-plain materials and have been thoroughly leached, they have relatively low exchange capacities, and they contain only very limited supplies of mineral nutrients.
The soils involved in the east north-central states were of the Wooster, Miami, Crosby, Brookston, Clarion, and Webster series. The first four are members belonging to the gray-brown podzolic group, which have been developed on glacial drift, some of which was of a calcareous nature. Those of the last two series are prairie soils, which have been developed from calcareous glacial drift.
The Colorado vegetables were obtained from areas, where the Laurel, Gilchrist, and Berthan series predominate. These soils belong to the brown and planosol groups, and are under irrigation farming. They are high in calcium carbonate and in available mineral nutrients.