We have not had to recommend an insecticide to control adult rice water weevils in several years, but yesterday we were called to a field where I took these pictures. They were in a field of water seeded Cheniere that was drained, but still damp at the time of the visit. The heavy feeding pressure is very evident as was some seedling disease.
The combination of the two was resulting in seedling death and stand reduction. To add insult to injury, the field had been hammered by hail about a week before. It was clear the plants could not take much more. Ironically, the field was planted with Dermacor treated seed which will control the larvae very well while having little to no impact on the adults.
There were so many adult weevils that while kneeling down in one spot I was able to count no less than 5 weevils. We could find them on the soil moving from plant to plant in the middle of the day when they are usually hiding in cracks in the soil. The farmer mentioned he had been under some security lights a few nights before and he had seen thousands of weevils flying around. We recommended a foliar insecticide.