It is likely a significant amount of herbicide will leach through the upper soil profile where the weed seeds and seedlings are given the rainfall we have received. We should have good activation of herbicides applied preemergence, but leaching is a real possibility and we may have a shorter period of time with residual control. The next step is to firm up the residual weed control with other herbicides applied with our contact herbicides (e.g., paraquat, Storm, Ultra Blazer, Cobra, Basagran.) We recommend overlapping residuals through early and mid-season. With the rains, I would be on the early side of getting the next residual spray in the field.