In 1989, the Canadian Interdepartmental Task Force on Pesticide Drift was established to develop a generic approach for the registration and regulation of pesticides in Canada. The generic approach will utilize the vast data base existing in the open literature to characterize downwind deposit profiles for varying application and meteorological conditions. Presently, the data base consists of a number of field studies relating to the aerial application to forests. Computer models are being evaluated against the data base and will be used to interpolate for conditions not found in the data base. The generic approach recognizes similarities in spray dynamics for different formulations and hence only incorporates product specific toxic data in linking fate to environmental impact. In this paper, the approach is used to compare the cases for the aerial application of biologicals and chemicals, for forest insect control. A similar approach can be used to estimate buffers for ground application.