Cicada killer wasps are the largest wasps native to North America and the most alarming-looking thing that might show up in your yard in July. Despite the size, females rarely sting, and males can’t sting at all.
The real problem is what they do to your lawn. Females dig deep burrows in bare or thin turf, leaving mounds of loose soil across the yard. Here’s how to identify them, when to act, and how to keep them from coming back.
If you’d rather leave the overseeding and turf repair to someone else, local lawn care professionals can help.
| Key takeaways |
|---|
| • Males are territorial but cannot sting; females rarely sting unless grabbed or stepped on. • Females dig burrows 12 to 15 inches deep in your lawn. • Dense, healthy turf is the best deterrent. |
What are cicada killer wasps?
Cicada killer wasps are the largest wasps in North America. Females range from 1.5 to nearly 2 inches long, with males up to 1.5 inches, according to Extension Entomologist Jonathan Larson at the University of Kentucky. They’re often mistaken for murder hornets, but they’re a completely different and far less aggressive species.
How to identify them:
- Body: dark orange on the head and thorax, gradually darkening to black on the abdomen
- Stripes: three light-yellow stripes across the abdomen
- Wings and legs: orange tinge
- Size: females 1.5 to 2 inches, males up to 1.5 inches
Cicada killers are active from late June through early September across the continental US, with peak activity in July and August. They’re most common east of the Rocky Mountains. As their name suggests, they hunt cicadas, which helps keep cicada populations in check.
Females do most of the digging and hunting. Each female can have multiple burrows over her short adult life, stocking each chamber with 1 to 3 paralyzed cicadas to feed the next generation of larvae, according to Timothy Gibb, extension entomologist at Purdue University. Males stay close to nesting areas to mate with emerging females, which is why homeowners often see clusters of them patrolling the same patch of lawn.
Pro tip: Because they’re not aggressive and play a beneficial role, most extension services recommend leaving cicada killers alone unless they’re damaging your lawn.
Are cicada killer wasps dangerous?
- To people: Rarely. Female cicada killer wasps “are not aggressive and rarely sting unless they are grasped roughly, stepped upon with bare feet, or caught in clothing,” Gibb says. Males are territorial and will fly directly at people for inspection, but they don’t have a stinger.
- To pets: Minor risk. Small dogs and cats that bite or paw at a female could get stung, but this is uncommon.
- To your lawn: This is the real concern. Each female digs one or more burrows 12 to 15 inches deep and up to 3 feet long, according to UK Extension. A large population can leave dozens of soil mounds across a lawn, particularly in thin or bare areas.
- To cicadas: Very deadly. Females paralyze cicadas with a single sting and drag them underground as live food for their larvae.
Well-known sting researcher Justin Schmidt has called cicada killers the “gentle giants of the wasp world” in National Geographic coverage of the species.
Douglas S. Richmond, Ph.D., professor and extension specialist at Purdue University, says cicada killers haven’t really changed, but public concern about them has grown. He says the renewed attention often comes from people spending more time outdoors and sharing photos online. The wasps draw attention because they’re highly visible, nest where people notice them, and “are easy to misinterpret as dangerous social wasps.”
Why do they dig in your yard?
Cicada killers prefer specific conditions:
- Bare or thin turf, because they avoid thick, dense grass
- Sandy or loose, well-drained soil, which is easier to tunnel into
- South-facing slopes and sunny spots, for warmth
- Edges along sidewalks, driveways, and garden beds where turf is often thin, and soil is easier to dig
If your lawn has thin turf from drought stress, foot traffic, or struggling grass growing in shade, it’s a more attractive target.
Read more: Signs of Lawn Pest Damage vs. Disease vs. Drought Stress
How to get rid of cicada killer wasps
For most homeowners, control isn’t necessary or even practical. If burrows are in a low-traffic area, just wait it out. Cicada killer season lasts 6 to 8 weeks, and populations decline on their own by early September.
Water drenching
Purdue Extension recommends soaking the soil around tunnel entrances with water. Cicada killers dislike wet soil and may abandon the site, looking for drier ground. This is the lowest-toxicity option and the safest around pets, kids, and pollinators.
How to do it:
- Use a garden hose to soak each burrow area for 5 to 10 minutes.
- Get the soil wet several inches down, not just on the surface.
- Repeat every 2 to 3 days during peak activity if the wasps keep coming back.
- Pair with steps to thicken your lawn so the soil is harder to dig.
This works best on smaller infestations.
Insecticide dust on individual burrows
Always read the product label and follow basic pesticide safety before applying anything to your lawn. For targeted control of small infestations:
- Wait until after dark when wasps are inactive.
- Apply insecticide dust (carbaryl or permethrin) directly into burrow openings.
- Leave undisturbed for 24 to 48 hours so that wasps carry the dust deeper into the tunnel.
- Collapse and fill the burrow once activity stops.
- Repeat as needed for new burrows.
Area treatment for heavy infestations
A labeled liquid insecticide (bifenthrin or permethrin) sprayed across the affected zone stops new digging and reduces the population.
How to do it:
- Apply in the early evening when wasps are returning to their burrows.
- Spray the soil surface across the visible activity zone, treating a buffer of 5 to 10 feet around the edges.
- Follow the product label for mixing rates, timing, and restrictions around pets and kids.
- Reapply every 2 to 4 weeks during peak season, especially after heavy rain.
For larger lawns or stubborn infestations, this approach works best paired with fall overseeding to thicken the turf where wasps were nesting.
Pro tip: Never pour gasoline into burrows. It’s a serious fire and environmental hazard with no real benefit over water or a labeled insecticide.
How to prevent cicada killer wasps
Preventing next year’s infestation is more effective than fighting this year’s:
- Thicken your turf. Overseed bare or thin areas in fall, because dense grass makes burrow digging difficult.
- Mulch bare soil. 2 to 3 inches of mulch in garden beds removes bare-soil nesting habitat.
- Water regularly. Cicada killers prefer dry, loose soil, so regular watering makes the soil harder to dig.
- Tidy your edges. They favor edges along sidewalks and beds, and crisp edging removes prime nesting habitat.
- Treat in May or June. A preventive bifenthrin application to last year’s problem areas can stop wasps before they emerge.
Read more: Spring Lawn Care for Cool-Season and Warm-Season Grass
FAQs
Yes. Young wasps spend the winter underground and come out the next summer as adults. Many return to the same spot to nest. Without fixing the lawn conditions that drew them in, expect to see them again next year.
Adults live for only 6 to 8 weeks each summer. Females spend most of that time digging burrows and hunting cicadas. The next generation overwinters underground and emerges the following year.
No. Cicada killers are native, solitary, and rarely sting. Murder hornets (northern giant hornets) are an invasive Asian species that were wiped out from the US in December 2024. They look alike in size and color, but murder hornets are far more aggressive because they swarm to defend their nest.
Hire a local lawn care pro
A thick, healthy lawn is the best long-term defense against cicada killers. If you’d rather leave the overseeding, turf repair, and fertilization to someone who does it every day, Lawn Love makes it simple. Get a free instant quote, pick a time, and a local pro will help you build the kind of lawn cicada killers avoid.
Main Image: An eastern cicada killer wasp carrying a paralyzed cicada. Photo Credit: Judy Gallagher / Wikimedia Commons / CC BY 2.0
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