With planting off to a much faster pace in Iowa in comparison to the neighboring states of Illinois and Wisconsin, questions start arising around soybean re­sidual herbicides.

Typically, weed control starts prior to the soybean’s emergence. However, in a wet year, that plan often changes when the beans are planted and a rain event occurs before the preemergence residual herbicide can be applied.

While these previous plans were formulated with the best weed...