Damage control/economic thresholds applied to forestry: A case study of scleroderris in red pin

The purpose of this study is to determine the financial feasibility of controlling scleroderris (the European strain) in red pine plantations. To achieve this, three objectives were established: (1) to explain threshold concepts from agricultural pest management, (2) identify the similarities between agricultural pest management and forest pest management and use these to construct an economic framework for forest pest management, and (3) to apply the general economic framework for forest pest management to the specific problem of scleroderris in red pine plantations. For the first objective, five functions were identified that are required to construct both threshold concepts. Problems associated with misspecification of the control and damage function were also addressed. Two threshold decisions, the entomologists' and the economists', were developed from the functions. These two decision rules were combined using a three-dimensional graph. The purpose of this is to increase understanding of the relation between the two views.;A general economic framework for forest pest management was developed using the agricultural threshold concepts. This framework was used to solve the problem of scleroderris in red pine. From this application it was determined that the economists' decision rule yields higher merchantable volumes and net present values than the entomologists decision rule. In the entomologists' decision rule, maximization of merchantable volume does not imply maximization of net present value.