Guess the Pest! Week 18 Answer: Corn Rootworm

David Owens, Extension Entomologist,

Congratulations to Bob Leiby for correctly guessing Corn Rootworm. This is a critter that I do not often see; they tend not to like sandy soil. However, there are areas in the state, particularly New Castle and western Kent Co. with heavier ground. Where corn is not rotated, they can build up to large numbers. Looking at such fields now for adult rootworm will inform pest management decision making for next year.

Wind damage is another close guess, especially now that we have had two tropical storms blow through. My sweet corn spray trial took a real beating the day before the first application was supposed to go out. The difference is that the field where the picture was taken hasn’t been rotated and had anywhere from 2 to 10 corn rootworm adults per plant.