Yellow Jackets

Yellow jackets are small, bright yellow-and-black social wasps that nest in the ground or inside walls and are responsible for most stings in American backyards. They're easy to tell from bees: smooth, shiny bodies, a sharp "wasp waist", and a taste for meat and soda that brings them to picnics and trash cans in late summer.

Are yellow jackets wasps?

Yes. They're social wasps (genus Vespula, plus Dolichovespula, the aerial yellow jackets) in the same family as hornets and paper wasps. "Yellow jacket bee" is a common but wrong name. Compared with bees they are hairless, shinier, more brightly patterned, and they hold their legs tucked in flight, not dangling like paper wasps.

Types of yellow jackets in the US

• Eastern yellow jacket (V. maculifrons): the most common in the East; ground nests.
• Western yellow jacket (V. pensylvanica): the West; ground nests; a notorious scavenger at picnics and campgrounds.
• Southern yellow jacket (V. squamosa): the Southeast; in warm areas some colonies survive the winter and grow to huge, perennial nests.
• German yellow jacket (V. germanica): introduced; often nests in walls and attics.
• Aerial yellow jackets (Dolichovespula), including the black-and-white bald-faced hornet, which builds gray paper nests in trees and shrubs. See hornets.

Where do yellow jackets nest?

• In the ground: most common. Look for a single hole, often the size of a quarter, with a steady stream of wasps flying straight in and out, especially in lawns, under shrubs, in banks and along foundations.
• In walls and attics: wasps going in and out of a gap in siding, soffits, around vents or window trim.
• In hollow logs, stumps, landscape timbers, old rodent nests and occasionally in parked equipment.
• Aerial: enclosed gray paper nests in shrubs, trees or under eaves.

A yellow jackets nest starts in spring with one queen and a walnut-size comb. By late summer it can hold 1,000–4,000 workers (much more for perennial southern nests), with a ground cavity the size of a basketball. Only new queens survive winter; the nest is abandoned and not reused.

What do yellow jackets eat?

• Spring and early summer: they hunt live insects such as flies, caterpillars and bees and chew them up for larvae. They're beneficial predators at this stage.
• Late summer and fall: colonies are huge, larvae fewer, and adults switch to sugars and scavenging: soda, juice, beer, ripe fruit, meat, fish, pet food and garbage.

This switch, plus the colony's peak size, makes August–October the worst months. Are yellow jackets pollinators? Only marginally; they drink nectar but carry little pollen.

Are yellow jackets aggressive?

They're the most defensive common wasp in the US:

• They defend the nest as a group, and vibration (mowing, trimming, stepping on the entrance) can trigger dozens of stings.
• They sting repeatedly and don't leave a stinger.
• A crushed yellow jacket releases an alarm scent that draws others.
• Foragers at food will sting when swatted or when trapped in a can or clothing.

If you run into a nest, walk or run away fast in a straight line and go indoors. Don't jump into water; they wait. First aid and warning signs: bee and wasp stings.

How to keep yellow jackets away

• Cover food and drinks outdoors; use cups with lids and check cans before drinking.
• Tight lids on trash and recycling; rinse sweet containers.
• Pick up fallen fruit; feed pets indoors.
• Hang yellow jacket traps (protein bait in spring–early summer, sweet or heptyl butyrate lures later) at the edges of the yard, away from seating. Spring traps catch queens before they start nests.
• In fall and spring, caulk gaps in siding, soffits, around pipes and vents.

How to get rid of yellow jackets

Ground nest (DIY when the nest is accessible and nobody is allergic):

1. Locate the entrance during the day from a distance. Mark it with a flag a few feet away.
2. Return after dark, when the colony is inside. Wear long sleeves, long pants tucked into socks, gloves and eye protection. Use a red-filtered light; white light draws them.
3. Puff an insecticidal dust labeled for yellow jackets (common actives include deltamethrin) into the entrance, or use a labeled aerosol foam. Dust is preferred because workers carry it deeper into the nest.
4. Don't plug the hole and don't stand over it. Check from a distance the next day; repeat if activity continues.
5. Pouring gasoline or burning the nest is dangerous, illegal in some places, and contaminates soil. Don't.

Wall nests: never seal the hole from outside: the wasps may chew through drywall into the house. Dust the entrance or call a professional.

Aerial nests: a wasp-and-hornet aerosol at night, from the label distance, or a pro for high and large nests.

What kills yellow jackets instantly? Contact aerosols knock down wasps they hit within seconds, but only the nest treatment ends the problem. Soapy water kills wasps it soaks but rarely reaches the full colony underground.

More detail and product types: how to get rid of wasps and wasp nests.

When to call a pro

• Nest inside a wall, attic, or crawl space.
• Nest you can't locate but wasps keep appearing indoors.
• Very large or perennial nests (in the South) or several nests.
• Anyone in the household with a sting allergy, or nests near play areas.

Professional treatment usually runs roughly $150–$450 per nest (approximate; wall and attic jobs cost more) and is typically done in one visit.