An Evaluation of the Effects of Log Length on Timber Values in Thinning (Abstract‪)‬

Abstract This research investigated an economic component of harvesting operations not previously studied for steep-slope thinning harvests in Douglas-fir (Pseudotsuga menziesii) stands in the Pacific Northwest. Of interest was the influence of allowable log lengths and the effect on revenues with a bucking-to-value strategy. Resulting log lengths influence revenues and logging costs important to forest managers, logging contractors, and mill managers. Here, a reduced set of log lengths was evaluated that approaches computer-generated optimal values and creates the potential for development of a bucking decision tool having the form of a bucking pattern cutting card. The reduced set of five log lengths (two mill-length logs and three woods-length logs resulting from combinations of the mill-length logs) was also compared with the full set of allowable lengths for value recovery and fiber utilization. Resulting values were 96 and 98 percent of full-set optimal values for 45- and 65-year-old stands, respectively. Value recovery exceeds that with current unaided bucking practices. The resulting bucking patterns can be easily incorporated into a cutting card based on length to merchantable top. This approach reduces the number of logs handled, increases mill-preferred long logs, decreases pattern count, and increases recovered value. Potential value gains of $4.09 to $8.80 per 100 cubic feet for the two stands are discussed with respect to mill constraints. Use of a combinatorial heuristic is suggested for matching produced logs to mill purchase orders. The board foot-to-cubic foot ratios used for the cubic foot-based analysis are also discussed.