Abstract A field experiment was undertaken on the Hanford Reservation in eastern Washington State during 1975 to study techniques for maximizing herbicide applications from a spray airplane on the intended area and minimizing drift. The design of the experiment was unique in that all components of the herbicide release (i.e., target application, downwind drift and drift residues, and the vertical distribution of drift) were monitored. Several early morning experiments were conducted which were designed to compare drift characteristics of a fixed application with those of a test application for various nozzle systems and herbicide concentrations. The results of these experiments showed that the initial drift and drift deposit components for various application techniques varied by only a factor of two or so, depending on the production of smaller droplets. Meteorological conditions become increasingly important at greater downwind distances from the source. Furthermore, drift reduction was most effective under conditions of high relative humidities and cool temperatures. At large distances from the source, ground level drift was higher on stable than on unstable days. The experimental results emphasize the importance of measuring all components of herbicide release to achieve the stated objective of identifying techniques to maximize the target application and minimize drift.