Leaching of dicamba in a coastal plain soil

Dicamba leaching to groundwater was studied for three years on an Evesboro loamy sand soil. Dicamba was applied to conventional tillage and no-tillage corn post-emergence at a rate of 0.56 kg/ha. The first year, dicamba was detected in all of the monitoring wells, 12 days after it was applied. Concentrations ranged from 2.0 to 37.0 mu g/L. A total of 54 mm of rainfall occurred in the 12 days. In years two and three, dicamba was detected infrequently in the groundwater. The highest concentration was 4.9 mu g/L. Other researchers have also found dicamba will move below the root zone if sufficient rainfall or irrigation occurs before significant degradation occurs.