Bald-faced hornet sting
What it looks like: A large, hot, red swelling with a central point, red. Pattern: often several — the colony defends aggressively. Onset: immediate severe pain. Worst at: 2 to 24 hours. Duration: swelling for several days.
| Looks like | a large, hot, red swelling with a central point |
|---|---|
| Pattern | often several — the colony defends aggressively |
| Size | 15–120 mm |
| Appears | immediate severe pain |
| Worst at | 2 to 24 hours |
| Lasts | swelling for several days |
| Itch | ●●●○○ 3/5 |
| Pain | ●●●●● 5/5 |
| Usually on | head, neck, arms |
| Active | June to October, daytime |
Not sure it is bald-faced hornet? The app reads the photo and names the likeliest cause. Download free iPhone & iPad · no account
How to tell it apart
Technically a large yellowjacket, black with an ivory-white face, and the most defensive of the group. Multiple stings during a single encounter are typical because the colony responds together and follows for a distance.
Where and when you meet it
Habitat: enclosed grey paper nests the size of a football, hanging in trees, on sheds and under eaves.
Across 35,412 verified US records in the GBIF biodiversity database, sightings of Dolichovespula maculata concentrate in July to October. That is the window when bites are most likely — it is observation data rather than a guess, and it shifts with latitude.
States with the most recorded sightings
- New York 3,286 records · all bites in New York
- Illinois 3,201 records · all bites in Illinois
- Minnesota 2,797 records
- Ohio 2,390 records
- Pennsylvania 2,291 records
- Massachusetts 1,932 records · all bites in Massachusetts
- Virginia 1,703 records
- Maryland 1,522 records
- Michigan 1,222 records
- North Carolina 1,131 records · all bites in North Carolina
- Wisconsin 1,131 records · all bites in Wisconsin
- New Jersey 1,090 records · all bites in New Jersey
Record counts reflect where people report and identify specimens, not exact abundance. They are useful for ruling a species in, not for ruling it out.
Where it is recorded
| Country | Records | Peak months there |
|---|---|---|
| United States | 35,412 | July to October |
| Canada | 12,005 | July to September |
| Germany | 19 | — |
Verified records from the GBIF biodiversity database across the seven countries we cover. A country missing from this table means we have no records for it, not that the species is absent.
What it means for you
Nests are annual and die off with the first hard frost, so removal is only urgent where people pass close by. Provocation from mowing or strimming under a tree is the usual trigger for a mass-sting incident.
Seek medical care if
Call emergency services now for difficulty breathing, swelling of the lips, tongue or throat, dizziness or fainting, or hives spreading away from the bite.
- breathing difficulty, throat tightness, faintness, hives away from the site
- multiple stings
- stings to the face or mouth
Care at home
- leave the area quickly — this species pursues
- cold pack, antihistamine, pain relief
- adrenaline auto-injector if prescribed
Preventing the next one
- never disturb an enclosed grey paper nest; have it removed professionally
- keep distance when mowing or strimming near trees
Common questions
Do bald-faced hornets sting humans?
Technically a large yellowjacket, black with an ivory-white face, and the most defensive of the group. Multiple stings during a single encounter are typical because the colony responds together and follows for a distance.
What does a bald-faced hornet sting look like?
A large, hot, red swelling with a central point, red. Pattern: often several — the colony defends aggressively. Size: typically 15–120 mm across.
Does a bald-faced hornet sting hurt?
Pain is very severe (5 out of 5 on this site's scale) and itch is noticeable itch (3 out of 5). Onset: immediate severe pain. Worst at: 2 to 24 hours. Duration: swelling for several days.
How do I know it was a bald-faced hornet?
Technically a large yellowjacket, black with an ivory-white face, and the most defensive of the group. Multiple stings during a single encounter are typical because the colony responds together and follows for a distance.
How long does a bald-faced hornet sting last?
Duration: swelling for several days. Worst at: 2 to 24 hours.
When is it a problem?
Seek care for: breathing difficulty, throat tightness, faintness, hives away from the site; multiple stings; stings to the face or mouth.
Can it transmit disease?
No human disease is known to be transmitted by this species in the United States. The practical risk is infection from scratching.
Get a photo assessment in the app
Everything above is free to read. The app adds what a page cannot: point your camera at the bite and get an assessment of the most likely cause, a severity read, and a day-by-day care plan — including the specific signs that mean you should be seen.
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