Orangeburg Soil Series

Orangeburg soil has a split personality: the surface is pale and gritty — sandy loam that crumbles in your hand — while the subsoil is vivid yellowish-red to red clay, stained by iron that has been migrating downward for thousands of years. That contrast is visible in every road cut across the South Carolina interior.

The soil is well drained and deep, which makes it naturally productive for row crops and pine timber. In its undisturbed state, it supported longleaf pine, loblolly pine, and turkey oak — the fire-maintained woodland that once covered most of the inner South Carolina Coastal Plain.

Soil scientists at the USDA Natural Resources Conservation Service selected the Orangeburg series to represent South Carolina because it is the most extensive and agriculturally significant soil on the state's inner Coastal Plain — the landscape that has shaped South Carolina farming since the 1700s.

The series is named after Orangeburg County in the center of South Carolina, where the soil was first formally described. Orangeburg County has been a hub of Coastal Plain agriculture since German and Swiss settlers established farms there in the 1730s.

The Orangeburg series is recognized by the USDA as South Carolina's state soil. It was selected because it captures the sandy, well-drained upland landscape that separates the river swamps and defines the character of the South Carolina interior.

Dig into Orangeburg soil and the surface is pale and gritty — sandy loam that crumbles in your hand. A foot below the surface, the sand gives way to a brighter, yellowish-brown transition zone. Keep digging and the soil turns unmistakably red: a sticky, iron-rich clay that marks the argillic horizon. The color deepens toward pure red at two to three feet, then fades back to pale yellowish brown as the ancient marine sediments return.

Orangeburg soil covers the gently rolling uplands of the inner Coastal Plain — the broad, level-to-undulating terrain that runs across the middle third of South Carolina between the Fall Line and the tidewater counties near the coast. Elevations range from 100 to 400 feet, with annual rainfall of 44 to 52 inches.

The series is concentrated in Orangeburg, Calhoun, Bamberg, and Barnwell counties at its center and extends north and south through Lexington, Richland, Sumter, Lee, and Williamsburg counties.

Tobacco has been the signature crop on Orangeburg soil for nearly 300 years. The well-drained, sandy surface that discourages many crops is exactly what flue-cured tobacco needs: fast drainage, warm soil temperatures, and low moisture retention that concentrates sugars in the leaf. South Carolina's tobacco belt runs directly through Orangeburg soil country.

Cotton, corn, soybeans, and peanuts are the other major row crops. Soybeans now exceed tobacco in total Orangeburg acreage as farm economics shifted through the late twentieth century. Sweet potatoes grow well on the sandier surface layers, particularly in the southern counties.

Loblolly pine plantations cover large areas of Orangeburg soil that were retired from crop production. Managed pine is a major industry across the inner Coastal Plain. Before European settlement, longleaf pine, turkey oak, and bluejack oak formed the open, fire-maintained woodland over most of this landscape.