The Calhoun Experimental Forest, a research area of the Southeastern Forest Experiment Station, was established in 1947 for work on Piedmont forest, soil, and water problems. Located in the Sumter National Forest, near Union, South Carolina, the forest was chosen hecause it represented poorest Piedmont conditions.
Since early settler days, the great Piedmont belt of rolling clay hills has undergone drastic changes. Not infrequently, a foot of topsoil has been lost. The subsoil is typically a tight, impervious clay that sheds water rather than taking it in and storing it. Channels of once-clear streams are now filled with eroded soil, and during rainy seasons the red creeks and rivers overflow their banks in wide swamps and floodplains.
Metz, Louis J. (1958): The Calhoun Experimental Forest. US Forest Service Southeastern Forest Experiment Station, June 1958.