John C. Calhoun Experimental Forest
The Calhoun Experimental Forest, located in the Sumter National Forest near Union, South Carolina, was established in 1947 for work on serious Piedmont forest, soil, and water problems. The Calhoun’s initial location was determined to represent the “poorest Piedmont conditions” of soil erosion and cropland abandonment. Early studies on the Calhoun were aimed at soil improvement and watershed restoration in order to find the cheapest, quickest, most effective ways to improve tree growth and soil structure, runoff and sedimentation, and increase soil fertility for plants.
Current research includes the long-running collaborative study with Duke University in which the biogeochemistry of soil and vegetation has been monitored, sampled, and archived since 1957. Techniques to control subterranean termites and impacts of even- and uneven-aged management on wood quality. Forests of the Calhoun are actively managed by the National Forest System to allow future research opportunities.
Three seriously eroded watersheds are being re-gaged to continue watershed experiments that began in 1947. The experimental forest has recently become one of the nation's nine Critical Zone Observatories in a long-term project that brings together 15 scientists from six universities, colleges, and the USDA Forest Service.
Key Personnel
Point of Contact
-
Person
Mac A. Callaham, PhD
Team Leader/Research Ecologisthttps://research.fs.usda.gov/about/people/mac.a.callaham
Treesearch Publications
- ROBERTO CARRERA-MARTÍNEZ, Melanie K. Taylor, DANIEL JONES, SEAN D. SCHOVILLE, BRUCE A. SNYDER, Mac A. Callaham. 2025. The unseen diversity of the semi-aquatic earthworms of the genus Sparganophilus (Oligochaeta: Sparganophilidae) from the Southeastern Appalachian Piedmont
- Michael Ulyshen, Cory K. Adams, Jacqui Adams, Susan B. Adams, Mickey Bland, Don C. Bragg, Chuck Burdine, Mac A. Callaham, Richard Chaney, Gregg Chapman, Patsy Clinton, Cinnamon Dixon, Jacob Floyd, Phillip Jordan, Tara L. Keyser, Stephanie H. Laseter, Rachel Mallinger, Virginia McDaniel, Bryan Mudder, C. Dana Nelson, Katherine Odanaka, A. Christopher Oishi, Shawna L. Reid, Samm Reynolds, Kevin Robertson, Daniel Saenz, Mary Anne Sayer, Nathan Schiff, Brian Scholtens, Joel Scott, Martin Spetich, Melanie K. Taylor, John Willis, Andrew D. Young. 2024. Spatiotemporal patterns of forest pollinator diversity across the southeastern United States
- ROBERTO CARRERA-MARTÍNEZ, DANIEL JONES, SEAN D. SCHOVILLE, BRUCE A. SNYDER, Mac A. Callaham. 2021. Two new species of Bimastos (Oligochaeta, Lumbricidae) from the Southern Appalachian Mountains, North America
- Daniel deB Richter, Allan R. Bacon, Sharon A. Billings, Dan Binkley, Marilyn Buford, Mac A. Callaham, Amy E. Curry, Ryan L. Fimmen, A. Stuart Grandy, Paul R. Heine, Michael Hofmockel, Jason A. Jackson, Elisabeth LeMaster, Jianwei Li, Daniel Markewitz, Megan L. Mobley, Mary W. Morrison, Michael S. Strickland, Thomas Waldrop, Carol G. Wells. 2015. Evolution of soil, ecosystem, and critical zone research at the USDA FS Calhoun Experimental Forest
- William B. Patterson, Michael A. Blazier, Steven L. Holtard. 2010. Pinestraw raking, fertilization and poultry litter amendment effects on soil physical properties for a mid-rotation loblolly pine plantation
- Cheng Piao, Todd F. Shupe, Les Groom, W. Allen Nipper. 2009. Research update for the treated wood reusing program at the Calhoun Research Station
- Mac A. Callaham. 2008. Special Section: Soil Ecology and Restoration Ecology
- T.R. Clason, J.C. Adams. 2002. Loblolly Pruning and Growth Characteristics at Different Planting Spacings
- E.G. Owens, J.R. Jorgensen, W.E. Walmer. 1975. Effects of various spacings on loblolly pine growth
- Louis J. Metz. 1958. The Calhoun Experimental Forest