Hi Janet,

Are you sure it's billbugs? We may also see other white grubs/caterpillars this time of year. Can you send a photo?

There are "rescue" treatments available, but we'd first need to diagnose the cause...(and it could be billbugs!).

Hi again,

I think this is cranberry girdler larvae; billbugs are more short and squat. But it's "one of the white grubs".

Just to clarify, does the lawn pull up easily (like pulling a toupee off the head)? Can you send some photos of the lawn too? Sorry, I know going back-and-forth isn't ideal!

You can always email me directly: <personal data hidden>

Hi again,

Thanks for the additional information. There are "rescue products" you can apply, such as Dylox (trichlorofon). While you could buy this yourself online (Amazon does sell it: https://www.amazon.com/Bayer-Dylox-Granular-White-Insecticide/dp/B00I976K8M), it might be easiest to contact a lawn care company. The product does need to be watered in well.

Also, you may have to reseed the area; but this could be done next spring once you determine how much of the area is actually killed.

We blogged about cranberry girdler last fall: http://csuhort.blogspot.com/2020/10/cranberry-girdler-rears-its-ugly-head.html

Next spring I would strongly encourage you to apply Scotts GrubEx to the lawn, between June 1-15 (not earlier!). This is a season-long control product (and will also control Japanese beetle). You can find this at any box store and you can apply it with a push-type fertilizer spreader, set to the correct settings. The amount you apply is extremely small, but it works really well. This product also has to be watered in well after application (with about 1" of water). Let me know if you have other questions!

Hi Janet,

If you want to kill the grubs now, you will need to apply the Dylox this fall, ASAP. The damage could get progressively worse as the webworms will continue to feed. They will also be moving deeper into the soil for winter, so killing this population now will help for next year.

And yes, you would use the GrubEX as a preventative for the 2022 season...this will kill any overwintered grubs and those that might take up residence next year. 

To reseed, you would want to rake some of the dead grass, but don't leave too much exposed soil. Then aerate the entire area, as best you can...it's a narrow space, but make lots and lots of holes. Then use a fertilizer spreader to reseed the area. Seeding rates:

Kentucky bluegrass: 3-5 lbs/1000 square feet

Perennial ryegrass: 6-8 lbs/1000 square feet

Bluegrass/ryegrass mix: 5-7 lbs/1000 square feet

If you wait to reseed in the spring, do not use a crabgrass preventer in April; you can also reseed this fall. Dylox won't affect the seed.