J. Régnière and B.J. Cooke
Cooke's model is a computer program, written in object-oriented C++ language, that simulates the effects of Bt sprays on spruce budworm populations. It is based on well-documented and validated sub-models of budworm development and feeding. It simulates several biological processes that are seen as critical determinants of efficacy: budworm development, survival and feeding, foliage depletion, parasitism by Apanteles fumiferanae Vier., Bt droplet ingestion, feeding inhibition, mortality, and degradation of Bt deposits by ultraviolet radiation and rain. The model has been extensively validated under a variety of application conditions. Cooke's model can be used as a research tool to investigate the intricacies of Bt-budworm interactions or as a decision-support tool in the design of optimal application strategies of Bt to protect forests against excessive budworm defoliation. The present document describes the model's inputs and outputs, explores its behavior, and provides a tutorial for its use under the BioSIM simulation control environment. The model's most critical inputs and its most urgent data needs are also discussed.