Prior to any pesticide application, evaluate the site. Scope out and document potential problems long before you make the application. Applicators must know the direction of prevailing winds and know exactly what lies downwind of any application, since some droplets will be carried downwind from the application site.
The topography of an area can create microclimates where the temperature, wind, air flow, and humidity may be quite different from adjacent areas. Some locations are more likely to develop temperature inversions or to channel drift down slope and cause injury over long distances. Analyze every site carefully and consider weather conditions before making any pesticide application.
Leaving untreated buffer zones next to sensitive areas may reduce the impacts from spray drift. Buffer sizes vary depending upon the pesticide being used, the sensitivity of the area, and other drift management options being used.
Authored by Jim Wilson, PhD South Dakota State University