Integrated Crop Management is published by the Department of Entomology , Iowa State University , Ames, Iowa. The last few weeks have brought an increase in calls concerning injury from herbicide drift, especially from burndown applications involving 2,4-D and glyphosate. The corn postemergence season is now in full swing and we anticipate that calls concerning injury resulting from herbicide drift will continue. Below is an applicator's guide to managing herbicide drift. Know the wind speed and direction at the application site Pay attention to wind speed and direction around building sites.
Wind speed is highly variable from one location to another and during the day.
A wind meter should be used on-location for each application. This information is required for commercial applicator records and highly recommended for all private applicators. A wind meter is a small, but important, investment in drift management. Use a wind meter to determine speed and direction. There is no magic wind speed at which applications must cease.