Estimating Optimal Thinning and Rotation for Mixed-Species Timber Stands Using a Random Search Algorithm
Bullard, S.H., H.D. Sherali, and W.D. Klemperer. 1985. Estimating mixed-species thinning and rotation using a random search algorithm. Forest Science 31(2):303-315.
The problem of optimal density over time for even-aged, mixed-species stands is formulated as a nonlinear-integer programming problem with numbers of trees cut by species and diameter class as decision variables. The model is formulated using a stand-table projection growth model to predict mixed-speciesg rowth and stand-structure. Optimal thinning and final harvest age are estimated simultaneously using heuristic random search algorithms. For sample problems with two species random search methods provide near-optimal cuttings strategies with very little computer time or memory. Optimal solutions are estimated for problems with eight initial species/diameter class groups, projected for up to three discrete growth periods. Such solution methods merit further study for evaluating complex stand- and forest-level decisions