A methodology for estimating production possibility frontiers for wildlife habitat and timber value at the landscape level

This paper presents a method for estimating production possibility frontiers when the objective is joint timber and wildlife habitat production. The developed method is a guided-search technique that iteratively changes stands to new harvest schedules based on the lowest marginal cost of habitat increases. To illustrate the technique, joint production of ruffed grouse (Bonasa umbellus) habitat and value from harvesting of aspen (Populus tremuloides Michx. and Populus grandidentata Michx.) stands is considered. A ruffed grouse habitat suitability model, with a focus on interspersion of four aspen age-classes, was used to evaluate habitat conditions. Aspen timber value was evaluated through use of growth and yield models in combination with discounted costs and revenues. The technique was implemented on a 261-ha land unit in Itasca County, Minnesota. The resulting production possibility frontier was estimated from analysis of only 2000 possible harvest schedule scenarios and was convex, indicating increasing marginal habitat costs. Habitat quality could be increased, to a maximum of 23%, at a cost of 25% of aspen timber value. Using 25 000 random harvest schedules, analysis of the underlying distribution of objective function values indicated that points on the estimated production possibility frontier consisted of values greatly exceeding the 99.99th percentile.