A paired watershed experiment to determine the effect of clearcutting and regeneration of pine on the Georgia Piedmont showed that the small stormflows on dry soil may be increased 50 percent or more, but that larger flood discharges from wet soil were increased only 10 to 15 percent, if at all. The annual flood is apt to be of the latter type. The reasoned conclusion is that concern about the effects of forest operations on downstream flooding of creeks and rivers is unwarranted. However, peak rates of discharge immediately below the operation increased 30-45 percent, resulting in a 55-percent annual increase in stormflow erosivity during the 4-year cycle of harvesting, site preparation, and machine planting. The increase in erosivity of stormflows following this typical southern forestry operation, when considered in light of the accompanying increase in erosion hazard due to soil disturbance, warns the forest manager to increase his vigilance over road design, the selection of regeneration methods, and the maintenance of streamside protection zones. Forest Sci. 30:424-434.
Document Type: Journal Article
Research Technician, School of Forest Resources, University of Georgia, Athens, GA 30602