The functional relationships between rainfall intensities and amounts, and the washoff of dicamba and 3,6-DCSA from turfgrass foliage were determined. Dicamba was applied to Kentucky bluegrass field plots and the turfgrass was subjected to 2 to 58 mm of simulated rainfall 18 to 48 h later. Rainfall was applied at an average intensity of 20.6 or 39.9 mm h−1. The 39.9 mm h−1 intensity reduced dicamba washoff by 10% for a given amount of rainfall. Washoff of 3,6-DCSA was independent of rainfall intensity. When averaged over intensities, washoff of dicamba was best described by the equation y = 1 − 0.341x0.187, and 3,6-DCSA washoff by the equation y = exp(-0.210x), where x represents millimeters of rainfall and y, the proportion of compound remaining on the foliage after rainfall.