Optimizing forest stand management with natural regeneration and single-tree choice variables

This article addresses the any-aged forest management problem with individual trees as the choice variables in integer programming models. In order to sustain the forest using natural regeneration, spatial proximity of seed trees is required for harvesting to take place in these models. This problem requires integer variables to avoid harvesting part of a tree, but it is remarkably integer-friendly. Solvability of large models is thus explored, along with the patterns of solution that can be recognized in smaller models. Results from these exploratory models are sensitive to initial forest conditions and do not display the steady state conditions typically assumed for uneven-aged management in the literature.