Developing and testing the applicability of a decision support system for the planning of juvenile jack pine thinning

Abstract

An investigation was made into the applicability of a model used to assist in planning the allocation of pre-commercial thinning to juvenile jack pine stands. The hypothesis of this study was that planning pre-commercial thinning of juvenile jack pine to focus on areas within a stand {e.g. high density areas with the largest potential for response) is cheaper and more efficient than allocating a "blanket" pre-commercial thinning over entire jack pine stands. The model incorporates machine costing models, pre-commercial thinning productivity estimates, stand density maps, and road networks to investigate the potential cost savings of detailed planning of pre-commercial thinning. Integration of a GIS database, remote sensing, and network analysis provided an experimental decision support system (DSS) for planning the allocation of precommercial thinning. The DSS was applied to two study areas in northwestern Ontario containing juvenile jack pine stands. Based on the case study results, there appears to be potential for a total cost savings of 12 to 25 percent by planning and focusing precommercial thinning treatments to key areas of a stand. Estimated cost savings were reduced as the stem density spatial pattern became more uniform and the average stand density approached the eligible density for thinning. Cost estimates were also found to be sensitive to the pre-commercial thinning productivity estimates. The planning model could be applied to other problems involving spatial components such as skidder trail planning in harvest blocks. Use of this DSS could assist in investigating the interactions between stand density patterns, pre-commercial thinning productivity, pre-commercial thinning equipment operational costs and allocations pre-commercial thinning treatments within a forest stand.