Manual felling time and productivity in southern pine forests
1997
Lortz, D. | Kluender, R. | McCoy, W. | Stokes, B. | Klepac, J.
Sixteen stands were harvested by either clearcut, shelterwood, group selection, or single-tree selection methods. Three of the stands had uneven-aged structure. The other 13 were typical, mature, even-aged stands. Harvest intensity (proportion of basal area removed) ranged from 0.27 to 1.00. Harvested sites were similar in slope, average diameter at breast height (DBH), and pre-harvest diameter distributions. Logging contractors used 1 to 3 sawyers with production chain saws on all 16 tracts. There was no difference in production rate between sawyers on the same stand. Factors affecting total felling time (in decreasing order of importance) were DBH of harvested stems, inter-tree distance, and harvest intensity. Total felling time (including walk, acquire, fell, and limb-top times) was inversely related to harvesting intensity and directly related to stem DBH and inter-tree distance. Felling productivity was found to be highest under high intensity harvests of large trees and lowest under low intensity harvests of small trees. Productivity was more sensitive to stem diameter than harvest intensity.
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