Application of Optimal Control and Optimal Regulator Theory to the ``Integrated´´ Control of Insect Pests

``Integrated´´ control of pest species refers to a combination of physical, chemical, and biological actions for purposes of regulation. Attempts at the theoretical optimization of pest control exist in the literature (find seven such studies cited in the reference section). These studies have been analytical studies with simplified models or have been dynamic programming studies with low-order models. In this correspondence the numerical solution of the two-point boundary value problem of the optimal control of pests is illustrated. Such procedures are often subject to convergence problems but always hold the promise of being applicable to higher order models. Linear quadratic regulation about an optimal open loop trajectory is illustrated by example. Another feature here is a description of a ``dollar cost´´ performance index. The effect of increasing ``marginal´´ cost of control (i.e., increase of the partial derivative of cost with respect to control) is demonstrated. One of the advantages of the numerical method utilized is that the order of the model can be increased to include a dynamic crop state. A dynamic crop state is necessary for the proper calculation of the cumulative economic damage by a pest.