Productivity of rubber-tired skidders in southern pine forests
Sixteen stands were harvested at intensities (proportion of basal area removed) ranging from 0.27 to 1.00. Logging contractors used one or two rubber-tired cable and/or grapple skidders. Harvested sites were similar in slope, tree size, and stand composition. Thirteen of the stands had even-aged structures while the other three were uneven-aged. Skidding time per cycle was directly related to skidder type, distance, and number of stems hauled, and inversely related to harvest intensity. Skidding productivity (grapple skidder, per productive hour) was sensitive to distance, stem size, number of stems in a load, and harvest intensity. Productivity was more sensitive to tree size than harvesting intensity.