The impact of a single insect infestation on stand and forest level wood supplies: Jack pine budworm and jack pine

Deterministic simulation models were developed for the purpose of evaluating the impact of a single non-catastrophic insect infestation on stand and forest level wood supplies. The methodology for the evaluations was to run model simulations "with" and "without" the impact of defoliation on stand growth and yield. Impact was assessed as the difference between the volume (or alternatively, the net present value) outputs for the simulations. The case study for the evaluations was jack pine (Pinus banksiana Lamb.) wood supply and jack pine budworm (Choristoneura pinus Freeman) for three forests with distinctly different age class structures. The three structures were immature, well distributed and overmature. In lieu of expected budworm population forecasts, vulnerability ratings of the forests were assigned and used for the model simulations. The evaluations were performed using both constant and variable stumpage prices, estimates of jack pine defoliation impact from literature sources, and for the forest level model: oldest first and opportunity cost harvest scheduling techniques (OFHST & OCHST).;Results showed that at the stand level an infestation always reduced volume and net present values (NPV). At the forest level both volumes and NPV's are affected only negligibly in the case of the well distributed and the overmature forest for OFHST and OCHST. In the case of an immature forest, there is a reduction in volume and NPV for OFHST while there is no effect for OCHST. (Abstract shortened by UMI.)...