Learning Center / Lawn problems
How can you tell if your lawn has grubs?
Look for brown patches that peel back like loose carpet, grass that feels spongy, and animals digging up the lawn. Grubs eat grass roots, mostly in late summer and fall, and they are far easier to prevent than to repair.
- By David Obeid, founder
- Reviewed
- 5 min read
The short answer
What are lawn grubs?
Grubs are the C-shaped, cream-colored larvae of beetles like Japanese beetles, and they live in the soil eating grass roots. A few are normal. A lot of them can cut the roots off a lawn badly enough that whole sections die.
Beetles lay eggs in the lawn in summer, and the young grubs feed hardest from late summer into fall, which is when the damage usually shows up.
Warning signs
What are the signs of grub damage?
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Grass that peels back like carpet
Tug on a brown patch. If it lifts easily with no roots holding it down, grubs have likely eaten them.
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Spongy turf
The lawn feels soft or springy underfoot where roots have been cut.
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Animals digging
Skunks, raccoons and birds tearing up the lawn are often digging for grubs.
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Brown patches that don't respond to water
Drought-stressed grass greens up after rain; grub-damaged grass doesn't, because the roots are gone.
Checking
How do you check for grubs?
Cut out a square foot of turf at the edge of a damaged area, a couple of inches deep, and fold it back. Count the C-shaped grubs in the soil and roots.
A few grubs per square foot is normal and the lawn can handle it. Roughly ten or more is usually enough to cause visible damage.
Prevention
Is it better to prevent grubs or treat them?
Prevent them. Preventive grub control goes down before the new generation of grubs hatches and starts feeding, and it stops the damage before it starts. Once a lawn has lost its roots, the dead areas need to be reseeded.
Grub control is included in our lawn care program, and it also covers fleas, ants and ticks. Areas grubs have already killed are best repaired with fall aeration and overseeding.
Related questions
What people also ask
Is grub control included in your lawn program?
Yes. Our fertilization and weed control program includes an insecticide application for grubs, which feed on grass roots, that also covers fleas, ants and ticks.
Will a lawn damaged by grubs grow back?
Grass whose roots have been eaten usually dies and needs to be reseeded. Early fall aeration and overseeding is the best time to fill those areas back in.
Do grubs cause moles?
Grubs are one of the things moles eat, but moles mostly eat earthworms, so grub control alone rarely gets rid of them.
Keep reading
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