A shortest path model for the optimal timing of forest harvest decisions

The management of National Forests is a complex problem in which resources are scarce and multiple uses often conflict. A key aspect of forest policy is the determination of how to manage the <I>timber </I>resources of the forest, as many of the nontimber resources are conditioned by timber levels and harvest activities. In this paper, we present a 0 - 1 integer programming model which is used to determine an optimal timber harvesting sequence for a single stand, or group of stands, over a particular planning horizon. The harvesting model is developed around the classic shortest path network-flow model and, as such, exhibits the unique solution characteristics of the shortest path problem. The integer programming model performs extremely well computationally, always solving exactly in all 0 - 1 variables in its relaxed linear programming form.