Approximately optimal forest rotation in a nonstationary environment

The problem of optimal forest rotation in a nonstationary environment can, in general, not be solved analytically. Even qualitatively characterizing how the solution changes over time is only possible in some special cases. In this paper, we consider an approximation of the true solution to the nonstationary problem. We derive an approximate harvesting rule by solving a sequence of stationary problems that assume the growth conditions at that point in time will prevail indefinitely. Each such problem can be solved using the classic Faustmann rule. We numerically compare this approximate solution to the true solution, both in terms of the harvesting rule and the resulting expected profits, for a wide range of scenarios. We find that the harvesting rules are very similar (mostly <1 $\lt 1$ % difference) and the profit losses associated with following the approximate rule are very small (less than 0.3%).