I've been fighting what I believe is billbug damage in certain areas of my lawn for the past couple of years. They're most likely bluegrass billbugs (very black). I've just applied some Grubex a couple of weeks ahead of the recommended application dates because of the really warm weather we've been having all spring to hopefully preempt their descent into the soil and roots.
Today I spotted a couple of billbugs in the lawn which means they're still out feeding and laying their eggs. I want to try and eradicate as many of them as I can before they lay more eggs.
What's the best pesticide I can use to attack them? I have some Bayer insecticide that's meant for trees, shrubs and lawns. It's the type that absorbs into the plant and kills whatever feeds on the plant. Any thoughts?