| Key takeaways |
|---|
| • Grass-eating and yard-dwelling pests are different problems that need completely different treatment approaches. • Damage from certain pests can mimic drought stress. Check the soil and grass for lawn insects before irrigating. • Surface feeders and underground pests need different products. One broadcast spray won’t cover both. |
Summer lawn pests like grubs, chinch bugs, and armyworms eat grass directly, leaving brown patches or bare soil. Others, like fleas and ticks, don’t damage grass but make your yard hostile. Knowing which you have changes how you treat it.
If you’d rather skip the detective work, Lawn Love connects you with local lawn care pros who can identify and treat pest problems fast.
Summer lawn pests quick reference
| Pest | Peak Season | Region |
| White grubs | June-August | All regions |
| Chinch bugs | June-September | Southeast, Gulf Coast |
| Armyworms | July-October | Southeast, Mid-Atlantic |
| Sod webworms | July-September | All regions |
| Billbugs | June-August | All regions |
| Mole crickets | April-October | Southeast, Gulf Coast |
| Spittlebugs | May-July | Southeast, Mid-Atlantic |
| Cutworms | June-August | All regions |
| Fleas | May-October | All regions |
| Ticks | May-August | Northeast, Mid-Atlantic |
| Fire ants | April-October | Southeast, Gulf Coast, TX |
| Stink bugs | August-October | Mid-Atlantic, Northeast |
Which lawn bugs eat grass (and which ones just live there)
Summer pests such as white grubs, chinch bugs, armyworms, sod webworms, billbugs, mole crickets, spittlebugs, and cutworms actively eat your grass. If your lawn has any of these, act quickly. The longer you wait, the more damage they can do, and the harder treatment gets.
Fleas, ticks, stink bugs, and fire ants live in your yard, but don’t damage the grass. Your lawn won’t die from them, but they can make your yard inhospitable if left untreated.
1. White grubs
What to look for: Cream-colored, C-shaped larvae up to 1 inch long with a brown head and six legs.
White grubs are the larvae of Japanese beetles, June beetles, and other scarab species. They feed underground on grass roots from June through August, causing turf to turn brown and lift cleanly from the soil, with no roots attached.
Treatment: Apply a preventive grub control (imidacloprid or chlorantraniliprole) in June before eggs hatch.
Dr. Daniel Potter, professor emeritus of entomology at the University of Kentucky, recommends chlorantraniliprole as a grub preventative, noting it selectively targets grubs and other lawn pests while posing little hazard to bees and predatory insects.
“Chlorantraniliprole is highly effective against Japanese beetle adults and grubs,” Potter says.
For active infestations, 6-9 grubs per square foot is when you should start thinking about treatment, but turf health is equally important.
“A dense, vigorous, well-watered lawn can often tolerate grub feeding that would cause visible injury in a drought-stressed or poorly rooted lawn,” says Dr. Douglas Richmond, professor of turfgrass entomology at Purdue University.
“So before treating, a homeowner should not only count grubs, but also ask whether the turf is otherwise healthy and whether the damage is actually progressing. In other words, grub numbers matter, but lawn condition often determines whether those numbers are actionable,” he says.
For confirmed infestations that are causing damage, use a curative product (trichlorfon).
Read more: How to Get Rid of Grubs in Your Lawn
2. Chinch bugs
What to look for: Black insects with white wings, about 1/8 inch long. Nymphs are reddish-orange with a white band across the abdomen.
Chinch bugs are tiny, but their damage is severe. Adults pierce grass blades and inject a toxin that blocks water uptake, killing the plant. Damage appears first in sunny, dry areas and spreads outward in irregular patches.
St. Augustine and Zoysia lawns are most susceptible during hot, dry summers.
Treatment: Apply a pyrethroid insecticide (bifenthrin, cyfluthrin) at the first sign of damage.
Read more: How to Get Rid of Chinch Bugs
3. Armyworms
What to look for: Greenish to dark brown caterpillars, 1–2 inches long, with pale yellow or white stripes along the sides.
Armyworms are caterpillars that feed in large groups, rapidly stripping grass to bare soil. An extreme infestation of 6 or more armyworms per square foot can devastate a lawn within 2 to 3 days.
They are most common in the Southeast and Mid-Atlantic in late summer. Watch for flocks of birds feeding intensely on the larvae in your lawn.
Treatment: Apply a pyrethroid or spinosad insecticide when larvae are small (under 1/2 inch).
Read more: How to Get Rid of Armyworms
4. Sod webworms
What to look for: Small tan or grayish caterpillars with dark spots, about 3/4 inch long. Adults are small buff-colored moths.
Sod webworms are small caterpillars that live in the thatch layer and chew grass at the crown, leaving ragged tan patches. As the adults lay eggs, you’ll see moths zig-zagging low over the lawn at dusk. Damage worsens during hot, dry spells.
Treatment: Apply a pyrethroid insecticide in the evening when larvae are feeding.
Read more: How to Get Rid of Sod Webworms
5. Billbugs
What to look for: Gray to black weevils about 1/2 inch long with a distinctive elongated snout. Larvae are white and legless.
Adult billbugs are weevils that lay eggs in late spring; the larvae hatch and feed on grass stems and roots throughout the summer. Billbug damage looks exactly like drought stress, with the grass turning tan, but it won’t green up when watered.
Treatment: Apply a preventive insecticide (imidacloprid, thiamethoxam) in late spring before eggs hatch. Beneficial nematodes are an effective organic option.
The tug test helps differentiate between grubs and billbugs. If brown grass lifts easily with no roots attached and the stem ends show fine, sawdust-like frass, billbugs are likely the cause. Grub damage lifts the same, but won’t have frass.
Read more:
6. Mole crickets
What to look for: Brown, cylindrical insects, 1–2 inches long, with enlarged, shovel-like front legs adapted for digging.
Mole crickets tunnel through soil, severing roots and leaving spongy, raised runways on the surface. Adults fly and mate in spring; nymphs cause the most damage through summer and into fall. Most common in the Southeast in bahiagrass and bermudagrass lawns.
Treatment: Apply insecticide (bifenthrin, carbaryl) when nymphs are small and near the surface. This is typically June-July, but can be into early August along the Gulf Coast.
Read more: How to Get Rid of Mole Crickets
7. Spittlebugs
What to look for: Small, brown, wedge-shaped insects about 1/4 inch long. Nymphs are pale yellow-green.
Spittlebugs are small jumping insects that leave frothy white masses on grass and plants. The nymphs hide inside the foam while feeding on plant sap. Spittlebugs rarely kill turf outright, but heavy infestations can yellow and weaken centipedegrass and St. Augustine.
Treatment: Insecticides are rarely needed in most home lawns. A strong spray of water dislodges the foam, exposing the nymphs. For heavy infestations, carbaryl is effective.
8. Cutworms
What to look for: Gray to brown caterpillars, 1–2 inches long, that curl into a C-shape when disturbed.
Cutworms are moth larvae that cut grass stems at or just below the soil surface at night, leaving circular bare patches. More common in newly seeded lawns and after wet periods that keep them near the surface.
Treatment: Apply a pyrethroid insecticide or Bacillus thuringiensis (Bt) in the evening. Bt is an effective organic option when larvae are still small.
Read more: How to Get Rid of Cutworms
9. Fleas
What to look for: Tiny, dark brown, wingless insects about 1/16 inch long with large hind legs for jumping.
Fleas don’t eat grass, but they thrive in shaded, humid areas: under decks, along fences, in spots where pets rest regularly. A serious indoor flea problem almost always traces back outside. Excessive pet scratching is the earliest warning sign.
Treatment: Apply a permethrin-based yard spray to shaded areas and pet resting spots. Treat pets and indoors at the same time for effective control.
Read more: How to Get Rid of Fleas in Your Yard
10. Ticks
What to look for: Eight-legged, oval-bodied arachnids ranging from poppy-seed size (nymphs) to 1/4 inch (adults). Color varies by species from reddish-brown to dark brown or black.
Ticks don’t damage grass, but they pose health risks to people and pets. They are most active from May through August. Wooded borders, stone walls, and dense ground cover are the highest-risk zones.
Treatment: Apply a tick-control spray (bifenthrin or permethrin) to high-risk zones in mid-to-late May.
According to Erika Machtinger, associate professor of entomology and vector-borne disease team lead at Penn State University, treating these areas in a targeted way “provides excellent control while minimizing environmental impact.”
Mulch-mow or completely remove fallen leaves rather than raking them to the border, which can increase tick density.
Read more: How to Treat Your Yard for Ticks
11. Fire ants
What to look for: Reddish-brown ants, 1/8 to 1/4 inch long.
Fire ants pose a real risk of stings to children and pets. They don’t eat the grass, but their mounds smother the grass beneath them. They are common across the Southeast, Gulf Coast, and Texas.
Treatment: Use the two-step method: broadcast a fire ant bait across the entire lawn, then treat active mounds with a contact insecticide 3–5 days later. Don’t disturb mounds before applying bait.
Read more: How to Get Rid of Fire Ants
12. Stink bugs
What to look for: Shield-shaped, mottled brown insects about 3/4 inch long with banded antennae.
Stink bugs gather on lawns and exterior walls in late summer as they search for overwintering sites. They don’t eat grass, but they show up in large numbers and emit a foul odor when disturbed.
Treatment: Outdoor insecticides have limited effectiveness. The most reliable option is to collect them manually in soapy water.
Read more: Stink Bugs in Your Yard and Home
FAQs
Most likely spittlebugs or leafhoppers. Spittlebugs are identified by the white foamy masses they leave on grass blades. Leafhoppers are slender, wedge-shaped, and jump when disturbed. They don’t leave foam; their feeding causes stippled, bleached, or yellowing patches that resemble drought stress.
Chinch bugs and sod webworm larvae are the most common small grass-eating insects. Adult chinch bugs are 1/5 inch long, light-colored bugs with black wing patches. They damage sunny, dry areas first, leaving irregular patches that spread outward and won’t green up with watering.
Sod webworm caterpillars are tan with dark spots and actively feed at night. They chew grass at the crown, leaving ragged tan patches that worsen during hot, dry spells.
Yes. A broadcast pyrethroid (bifenthrin, permethrin) controls most surface-feeding pests simultaneously: chinch bugs, armyworms, sod webworms, fleas, ticks, and cutworms. Grubs and billbugs require a separate soil-active product, since they feed underground.
Yes. Bacillus thuringiensis (Bt) controls caterpillar pests, including armyworms, sod webworms, and cutworms. Beneficial nematodes are effective against grubs, billbugs, and mole crickets. For Japanese beetle grubs specifically, milk spore is a long-term organic option that establishes in the soil over time.
Not sure what’s eating your lawn?
Effective lawn pest control takes practice, the right equipment, and time you may not have. If you’d rather skip the guesswork, Lawn Love makes it simple. Get an instant quote, pick a time, and a vetted local pro will handle your summer lawn pest problem.
Get a free estimate near you →
Related Posts:
- Guide to Using Pesticides on Your Lawn
- Integrated Pest Management for the Lawn
- Signs of Lawn Pest Damage vs. Disease vs. Drought Stress
Main Image: A close-up of a shield bug, a common outdoor pest that emits a foul odor when disturbed and can damage garden plants and turf. Photo Credit: Illuvis / Pixabay
Related Posts:
