Ask Burton: This week, we’re talking about the single largest issue brought to us over the past few days. The armies are marching! Q: My Bermuda lawn has had huge patches turn brown almost overnight – and there are literally thousands of caterpillars all over the place. My lawn, my patio after the rain, everywhere. Help!

A: These are armyworms, and this weekend, we spoke to so many folks who had this issue that it seemed like every other customer had this problem.

Armyworms chew the foliage of your lawn grasses, usually leaving a clear web of background fiber after feeding on the juiciest layer of the leaf blades. They’re capable of multiple generations per season, and are likely to be a problem for the next six weeks or so. They thrive on tender grasses growing after extensive rainfalls… and they eat most of the foliage they’ll consume in their last three days before pupating into an adult. This is why the damage is so extensive, so recent, and seemed to happen all at once for you, because it did.

Several insecticides will work, but we prefer two. Treat with Bonide Insect & Grub Killer, mow the turf down a little bit to remove damaged foliage, fertilize if you haven’t already for fall, and hold what you have. For organic maintenance customers or customers with pets, B.T. based products (fertilome Caterpillar Killer) are a very safe, effective alternative, but you’ll have to apply it several times as the product doesn’t stay active long. Thankfully, this pest doesn’t damage root systems, but you will want to stop it from making your lawn look awful and forcing the turf to regrow damaged leaves instead of storing those nutrients for winter.