- Jones Jr., Earle P.
USDA Forest Service, Southeastern Forest Experiment Station, Dry Branch, GA
During 7 years before seed-tree harvest, plots in a mature Georgia Piedmont loblolly pine stand received one of four treatments: annual winter fire, 3-year periodic winter fire, 3-year periodic summer fire, and unburned check. Vertical projection of the 8-foot tall understory, which was measured annually in the fall, initially showed that 60 percent of the understory was of species that compete with pine regeneration. Average 7-year effects were that all burns reduced hardwoods 15 percentage points, while hardwoods increased 12 percent on check plots. Herbaceous cover increased 18-24 percent on winter-burned plots and 3 percent on summer-burned plots. Vines were not significantly reduced by burning. Burning at 3-year intervals was more effective than annual burning, and periodic summer fires gave best results.