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This purpose of this study was to assess ground disturbance from harvesting hardwood stands with conventional rubber-tired skidders on slopes greater than 30 percent in Virginia. Special emphasis was placed on erosion, compaction and soil movement. Ten randomly selected study areas were clear-cut between September 1988 and August 1989; measurements followed between March 1989 and August 1989. Potential erosion was estimated using the Universal Soil Loss Equation and soil mechanical strength was measured with a cone penetrometer. Volumes of soil movement resulting from skid trails, landings, and waterbars were measured. Circular plots were used to estimate the percentage of each tract in seven disturbance classes. Descriptive data documented during the study includes land ownership, precipitation records, soil survey information, equipment (make, model, tire size), and volume of the products removed during harvesting. Results show a relatively small amount of soil disturbance associated with harvesting these tracts. Erosion estimates for seven of the ten tracts were below 1.08 tons/acre/year and only one was greater than 3.0 tons/acre/year. The erosion potential for these areas will decrease with time as vegetation increases. The primary source of ground disturbance within the harvested areas was due to skid trails, which occupied 3 to 10 percent of the ground surface. Tracts using overland skid trails experienced far less disturbance than those with bladed skid trails. Following harvest, the undisturbed area ranged from 73 to 81 percent on the ten study tracts. Scheduling practices, tract layout, and tract closure techniques concentrated in high risk spots, can greatly reduce the impact of harvesting steep slopes. / Master of Science