Common in summer
Grubs in the Lawn: Signs and How to Check
Grubs are beetle larvae that chew grass roots below the surface, leaving patches that brown out and can be rolled back like loose carpet. They're a common late-summer cause of dead patches — but only worth treating when you actually confirm enough of them, so a quick count comes before any product.
How to tell
- Irregular brown patches that feel spongy underfoot because the roots are severed.
- Turf that peels or rolls back easily, with no anchoring roots underneath.
- Skunks, raccoons, or birds digging up the lawn at night to eat the larvae.
- White, C-shaped larvae in the top inch or two of soil when you peel back a patch.
What to do
- Step 1
Cut a flap and count
Peel back a one-foot square of turf at the edge of a damaged patch and count the white, C-shaped grubs. A few are normal and harmless; control is generally only warranted when counts run high (often cited around 8–10+ per square foot for many grasses).
- Step 2
Support recovery first
A healthy, well-watered lawn outgrows light grub feeding. Keep it watered and mowed high so it can repair the root damage on its own where counts are low.
- Step 3
Treat only a confirmed infestation
If the count is genuinely high, choose a product labeled for grubs and match it to the timing on the label (curative vs. preventive products work at different life stages). Repair killed patches once they're gone — reseed cool-season lawns in fall, or plug/sod warm-season grasses like St. Augustine.
Always read and follow the product label — it is the legal authority on rates, timing, and safety. These windows are regional estimates, not a prescription; defer to the label and your local extension office.
Not sure this is the one?
Grubs is one of several causes that look alike from the porch. Answer a few quick questions in the free diagnosis tool and it checks your symptoms against all of them — and what to do about each — no signup required.
Diagnose my lawnPreventing it next season
A deep-rooted, properly watered lawn tolerates grubs far better than a stressed one. Where grubs are a yearly problem, a preventive product applied at the labeled time is more effective than chasing damage later.
Frequently asked questions
- How do I know if I have grubs or just drought?
- Drought-browned grass stays rooted and perks up with water; grub-damaged turf lifts or rolls back because the roots are chewed off. Peel back a patch edge and look for white, C-shaped larvae to confirm.
- How many grubs are too many?
- A few grubs per square foot are normal and don't need treatment. Damage usually only shows up at higher counts, so do a one-square-foot count before treating, and follow the product label for the threshold and timing.
Grubs by grass type
The signs and the fix shift with your grass — its season, whether it self-repairs, and what it's sensitive to. Pick your grass for guidance tuned to it: