They damage lawns? Should I carpet bomb the grub ex? I did put out down Bug b gon, but not sure if that’s effective.

Grubs eat organic matter. If they are in a bed that is well amended with compost, they'll just eat that compost. If under a lawn, they'll eat the grass roots, because that's the only organic material around.

Why would you kill them? Are they causing damage?

Grubs can seriously damage lawns. Large patches of dead grass. But if you don't see any damage, don't worry about them.

At numbers greater than ten per square foot, they can cause damage. But if you don't see any damage, disregard them.

GrubEx won't do much, if anything, to those--they're just about to pupate and turn into mature insects.

To suppress them in the future, use GrubEx at bag rate when advised on the bag for your area (it's a pretty safe suppressant as opposed to trying to kill what you have, which is far more toxic). For me, that's May.

I always do, but tend to have a bit of an issue. One year, I had thousands of square feet of turf float due to having the roots eaten. Digging showed uncountable grubs per square foot in September and I had to pull out the big guns. That's unusual, but it was a dry year and I had the only decent turf for miles. It must have been a beacon in July.

So now I suppress it out yearly and use traps. Yearly, the number of Japanese beetles (the cause of my particular grub problem) has decreased from "yuck" to practically nothing. I also render the most-tasty shrubs and plants toxic to them.

unless it's lawn, it's not the damage they do at that stage that is a problem.. it's after they evolve into the final stage that they become a problem, especially if you have a vegetable garden. they are likely beetles, and they will start emerging late may and june.

Beneficial nematodes work well, at least they do for me. Application is a bit fussy, but they do work. I don't need as many chafer bugs as Nature thinks I do, so I squish the grubs as I find them (I wear gloves - not that brave as to do it bare-handed).

Kind of depends on what they are. Around here, they are mostly June bugs, which might do a little foliage damage, but are not devastating. Birds feast on them. Japanese beetles are much more serious to the vegetable gardener. Your local extension service would probably be able to tell you what kind of pest you're dealing with.