• Lawn grubs can cause major damage to your lawn, killing grass by eating the roots.
• Dead grass, animal and bird activity, and loose turf are common signs you might have lawn grubs.
• Lawn aeration and natural insecticides are two good options to get rid of and prevent lawn grubs.

Lawn grubs are pests that feed on your lawn. Lurking at the roots, grubs can wreak damage before you notice it. Yet if you know how to spot signs of lawn grubs, you can catch them in time.

We spoke to entomologists and lawn care experts about signs you have lawn grubs and safe solutions for getting rid of lawn grubs.

Meet the Expert

• Shannon Harlow-Ellis is an entomologist and a manager at Mosquito Joe.
• Casey DeLoe is Lawn & Arbor Branch Manager at JP McHale Pest Management.
• Steve Corcoran is a lawn expert and CEO of Lawn Love.

What Are Lawn Grubs?

Lawn grubs are insects in the larval stage, and the type of insect depends on your region, according to entomologist Shannon Harlow-Ellis.

"Lawn grubs, for example, might be the larvae of Japanese beetles, June bugs, Southern masked chafer, or Crane fly larvae," Harlow-Ellis says.

Lawn grubs are white and C-shaped, about 1/2-inch long. Their heads are usually a different color: solid brown, gray, or sometimes mottled. They have multiple pairs of legs.

Signs of Lawn Grubs

Dead or dying grass is the first clue that your lawn might have grubs. Loose or spongy turf and excessive animal or bird activity provide further evidence that your lawn has a lawn grub problem.

• Dead grass: Brown or dead patches of grass are often your first sign that your lawn may have grubs.
• Animal digging: You can tell that you have grubs if you have excessive animal digging in the late summer or early fall, says Casey DeLoe.
• Bird activity: Birds may infest your lawn in significant numbers, all looking for food in the form of lawn grubs.
• Loose turf: Sections of turf may pull up like a carpet as the root system detaches from the soil.
• Spongy grass: Turf excessively worked over by animals and birds will begin to feel loose, hollow, and spongy underfoot.
• Visual evidence: Coring to 3 inches or more will usually pull up deeply embedded lawn grubs. You may also see lawn grubs on the bottom of loose turf.

Why Grubs Are Harmful

Grubs harm a lawn because "the larvae feed on grass roots, damaging them so that they can no longer absorb water or nutrients," says lawn and arbor expert Casey DeLoe.

Harlow-Ellis adds that grubs invite other problems: "Predators of grubs can be an even bigger problem for your lawn. Raccoons, skunks, crows, and moles feed on lawn grubs."

This domino effect starts as dead patches in the lawn and rapidly cascades into widespread damage, eventually causing the lawn to die off.

Grubs vs. Similar Problems

It's essential to know how to distinguish lawn grub damage from other common issues because they tend to look alike.

Many things can be mistaken for grub activity, including disease, drought, sod webworms, and shade, Harlow-Ellis says.

But how can you know which is which? Harlow-Ellis says you have to get down to the roots—literally.

"Scouting your lawn for grubs is the best way to get confirmation," she says. "This can be done by using a shovel or edger to cut small sections of the lawn where these dark patches of dead grass appear."

How to Fix a Lawn Grub Problem

Chemical insecticides are always an option to get rid of grubs, says lawn expert Steve Corcoran. But you have to consider the negative consequences.

With so many safe solutions at your disposal, chemical insecticides are a last resort for preventing and dealing with lawn grubs.

Reduce Insect Population

To eliminate insect larvae, eliminate the insect in its adult stage. DeLoe suggests scouting around various plantings on your property around mid-summer. This is when the larvae have turned into adult insects and start feeding on the leaves of host plants.

"You can treat these adult populations in July to help reduce grub damage in the fall," DeLoe says. "The adults like to feed, mate, and then lay their eggs in the soil to mature later and eventually feed on your grass roots."

Remove Host Plants

Another way to prevent grubs is to remove host plants from around the lawn, DeLoe says. This guides lawn grub activity off-site and away from the lawn.

Lawn Aeration

Lawn aeration can reduce lawn grubs, Corcoran says. As a residual benefit, pulling up lawn cores from aeration may help you see grubs buried deep within the roots.

Natural Products

Harlow-Ellis says one natural product that helps control grubs is milky spore powder. This powder uses a bacterium, Paenibacillus popilliae, to target Japanese Beetle larvae.

Corcoran suggests using neem oil.

"It won’t directly kill them," he says, "but it will make it very difficult for them to survive, as it makes it difficult for them to get oxygen."