Recent Developments in Pesticide Application by the United States Animal and Plant Health Inspection Service1

Aerial application of pesticides is generally the method used by the United States Department of Agriculture (USDA) in the control of pests of rangeland, cultivated crops, and forested areas. With increased restrictions placed on pesticides, then- continued use requires improved application technology to meet acceptable levels of risk at reasonable cost The Animal and Plant Health Inspection Service of USDA is developing an aerial spray drift model for use by their field personnel to minimize drift from aerial application of pesticides to environmentally sensitive areas. Input information utilizing a low cost, field-deployable microcomputer includes aircraft type, application technique and hardware, pesticide formulation, meteorological conditions, and type (roughness) and extent of the site. Expected output computations will be: 1) distribution pattern of downwind deposition, including evaporation corrections and matching to empirical field measurement; 2) optimal aircraft swath spacing; and 3) buffer distance between the target area and the environmentally sensitive areas.