Logging planning, felling, and\ud yarding costs in five alternative\ud skyline group selection harvests

Graduation date: 1993Alternative silvicultural systems, such as group\ud selections, have recently come into vogue in the U.S.\ud Pacific Northwest in response to political and public\ud pressure against traditional, even-aged silviculture. There\ud is also interest in silvicultural systems for multiple\ud resources. Little is known about planning logistics,\ud operational requirements, and harvest costs for timber and\ud site conditions of alternative silvicultural systems. Much\ud of the terrain demands expensive cable logging systems\ud requiring up-to-date production and cost information for\ud harvest planning and administration.\ud This paper describes logging planning and harvest\ud requirements, production, and cost results of an\ud interdisciplinary experiment comparing alternative\ud silvicultural systems for multiple resource management. The\ud study was conducted in Oregon Coast Range, second growth\ud timber using five types of group selection harvest setting\ud designs. Skyline group selections were compared to a\ud clearcut. Group sizes ranged from 0.5 to 3 acres (0.20 to\ud 1.21 hectares). Group shapes included rectangular to\ud polygonal and wedge-shape, with parallel and fan shaped\ud setting skyline road plans. Harvest units were assessed for\ud their efficiencies and/or inadequacies for unit planning and\ud layout, felling, and yarding production and cost.\ud In group selection units, total harvest costs increased\ud from 7.3 to 31.5 percent over clearcutting. Patch size had\ud the largest influence over total costs (i.e. larger size;\ud lower cost). Total cost was also related to skyline setting\ud road plan and shape. Harvest cost components were greater\ud for group selection units than the clearcut.\ud Felling costs increased a minimal amount (0.4 to 2.6\ud percent) over clearcutting in most of the group selections\ud because of the need for more directional tree wedging.\ud However, standard yarding costs were estimated to be\ud slightly lower than the clearcut (0.2 to 4.2 percent) in all\ud group selections due to increased frequency of turn\ud presetting. The wedge-shape group selection unit exhibited a\ud 52 percent lower road change cost over the clearcut. Other\ud group selection units were more costly (1.6 to 107.8\ud percent) than the clearcut road/landing change cost. The\ud amount of timber volume removed was a key factor affecting\ud the final yarding cost. Final yarding costs for all group\ud selection units increased 3.4 to 26.0 percent over\ud clearcutting.\ud Logging planning is the key to operationally efficient\ud and cost effective group selection harvesting. Although such\ud planning required 2.6 to 5.9 times more planning time and\ud cost commitment as the clearcut, lack of such planning would\ud cause other harvest costs to escalate as a result of\ud increased operational difficulties