M Anual Felling Time and Productivity 1n Southern Pine Forests S Tand Treatment

Sixteen stands were harvested by either clearcut, shelterwood, group selection, or singletree selection methods. Three of the stands had uneven-aged structure. The other 13 were typical, matrJre, even-aged stands. Hmest intensity @roportion of basal area removed) ranged from 0.27 to 1 .@I. Hanrestcd sites were similar in slope, average diameter at breast height (DBH), and pre-harvest diamcte.r distributions. Logging con&actors 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-treedistance, 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 diametw than harvest intensity. This is the first in a series of reports evaluating harvesting productivity and profitability as a function of harvest intensity. In this paper, manual felling operations are evaluated. The next installment evaluates skidding productivity. The final paper considers al1 harvesting phases and identifies key relationships between harvesting quipnient and the stand, with an emphasis on ha&sting profitability. Comparisoris of even-aged and uneven-aged forest management have recently attracted increased attention. Research in this area includes comparisons of the time required to perform various timber harvesting operations under differing management regimes. Manual tree felling is the most labor-intensive COW ponent of aII hal-vcsling operations, and Ircquedy reprcscncs a “bottleneck” 111 production. While mechanical felling is lypically mof-c pl-oductive than manual felling, site disturbance and residual stand damage are increased by the additional machinery operating on the stand. This, combined with the fact that unevenaged management requires more entries into the stand at shorter. intervals than even-aged prescriptions, makes manual felling a less intrusive alternative to mechanical felling. Also, steep slopes may preclude the use of mechanical fellers. Manual felling is and wilI contintie to be an important component in modezn forest management. Previous studies often addressed only a single harvest method, (i.e.. clear cutting or single-tree selection) (5,6) with differences among stands or harvesting crews and equipment confounded with treatment ef%cts (2.7.9). Studies have been needed that cover both even-aged and uneven-aged silviculture and contain a data set large enough to identify trends common to 41 manual felling operations. The results of felling time studies conducted over 4 years are presented here.