Wasps, Hornets and Yellowjackets: Identification, Nests and Safe Control

There is a nest under the eaves, wasps are diving at your soda, or something is flying in and out of a hole in the lawn. The first step is figuring out what it is, because the right answer for a paper wasp nest is very different from the right answer for a yellowjacket nest inside a wall or a honey bee swarm on a branch. This guide helps you identify the insect, decide whether it needs to go, and judge whether the job is safe to do yourself.

How to identify wasps, hornets, yellowjackets and bees

Wasps have smooth, shiny bodies and a narrow waist. Bees are fuzzy and stockier. Within the wasps, the shape and color, and above all the nest, tell you what you have.

Bees: protect them, do not spray them

Honey bees and bumble bees are pollinators, and most bee problems solve themselves.

• Honey bee swarm (a big cluster of bees hanging on a branch, fence or eave): swarms are usually gentle and move on within a day or two. Call a local beekeeping club or beekeeper, who can collect it. Do not spray it.
• Honey bees living inside a wall: an established colony in a building usually needs professional removal, and the job can involve opening and repairing the wall. Start by calling a beekeeper or a company that does live bee removal.
• Bumble bee nest in the yard: colonies last one season and die out on their own. Fence off the entrance with a bit of chicken wire or garden fencing so nobody steps on it, and seal any entry into the house after a hard frost or two.

Signs of a nest

• A steady stream of wasps flying in and out of one hole in the ground, a gap in siding or a soffit vent.
• A paper comb or gray paper ball under eaves, in shrubs, or in a shed.
• Wasps scraping at wooden fences, decks or furniture. Yellowjackets gather wood fiber to make their paper nests.
• Wasps inside the house in late summer or fall, which can mean a nest in a wall or attic.
• Mud tubes on walls or ceilings (mud daubers, which are low risk).

Why stings spike in late summer

Social wasp colonies start each spring from a single queen. By late summer, yellowjacket colonies are near their peak size, and the workers switch to scavenging sweets and protein. That is when they crowd picnics, trash cans, pet food dishes and fallen fruit, and when people run into ground nests while mowing or gardening. Wasps get more defensive as colonies grow through the season. In areas with cold winters, the colony dies off in late fall, and the old nest is not used again.

Here is how to cut down on encounters:

• Keep food and drinks covered outdoors, and look inside a can or cup before you sip.
• Use trash cans with tight lids and keep them away from patios and doors.
• Pick up fallen fruit and clean up spills.
• Do not swat. Move away calmly.
• Walk the yard in summer to check for ground nests before you mow.

Risks and sting safety

For most people a sting means pain, redness, itching and swelling that fades within a day or so. Yellowjackets can sting more than once, and a disturbed colony can deliver many stings at a time, which is dangerous even for people who are not allergic.

First aid for an ordinary sting:

• Move away from the area.
• Wash the site with soap and water.
• If a stinger is left in the skin (usually from a honey bee), scrape it out with a fingernail or wipe with gauze. Do not squeeze it or use tweezers.
• Apply ice. Avoid scratching. An antihistamine can help with itching; follow the package directions.

Allergic reactions are an emergency. Call 911 or get to emergency care right away if someone has hives, swelling of the face or throat, trouble breathing or swallowing, dizziness, or a racing pulse after a sting. Anyone with a known sting allergy should carry an epinephrine auto-injector as prescribed and still go to the emergency room after using it.

How to deal with wasps and nests, step by step

1. Identify the insect. Use the table above. If it is a bee, see the bee section and do not spray.
2. Decide whether it needs to go. A nest high in a tree or at the back of the property, away from doors and play areas, can often be left alone until it dies off in fall. Mud daubers rarely need any control.
3. Remove what attracts them. Cover trash and food, and clear fallen fruit.
4. Use traps for yellowjackets, with realistic expectations. See the traps section below.
5. Treat small, reachable nests yourself only if it is safe. See the DIY section.
6. Call a professional for the rest.

Yellowjacket traps: what they can and cannot do

• Lure traps baited with a chemical attractant catch foraging yellowjackets. The common attractant works mainly on the western yellowjacket. Some traps use meat or another protein bait, which needs frequent replacing.
• Water traps hang a protein bait over a container of soapy water. They work best in late winter and early spring, when they catch queens before colonies form.
• Placement: hang traps around the edges of the area you want to protect, away from where people sit. Traps near your table draw more wasps toward you.
• Limits: traps reduce the number of foragers but do not wipe out a large late-season population. They do nothing about a nest.

DIY vs professional treatment

A reasonable DIY job: a small paper wasp nest you can reach from the ground.

• Use an aerosol labeled for wasp and hornet nests and read and follow the label.
• Treat at night or at dusk, when the wasps are home and less active. Stand to the side, not directly under the nest.
• Wear long sleeves, long pants and gloves, and have a clear path to back away.
• Do not shine a flashlight straight at the nest entrance.
• Wait a day or two, make sure there is no activity, then knock the nest down.

Read using pesticides safely before buying any product.

Call a professional for:

• Nests in walls, ceilings or behind siding. Never seal the entrance hole. Trapped wasps may chew inward and come out inside the house.
• Yellowjacket ground nests near walkways, play areas or the lawn you mow. Treating them usually takes insecticide dust applied into the entrance at night, and a misstep can mean many stings.
• Bald-faced hornet and European hornet nests, especially large or high ones. Professionals use protective suits and veils for these.
• Any nest that needs a ladder. Getting stung while on a ladder is a serious fall risk.
• Anyone in the household with a sting allergy, or anyone who is not comfortable doing the job.

Our guide to choosing a pest control company explains what to ask before you hire, and pest control costs explains what affects the price.

Never pour gasoline on a nest or try to burn it. It rarely kills the colony, it can start a fire or injure you, and it often leads to multiple stings. Spraying a nest with a garden hose has the same problem.

Wasp and hornet questions

Will they reuse last year’s nest? No. In areas with cold winters, colonies die off in late fall and abandoned nests are not reused. New queens start fresh nests in spring. In very mild climates a few yellowjacket colonies can survive the winter.

Why are big hornets hitting my windows at night? That is most likely a European hornet. They fly at night and are drawn to lights. It is not an attack.

Should I knock down a nest early in spring? For paper wasps, yes. A newly started nest has only the founding queen, and knocking it down early usually sends her to build somewhere else. Check eaves, deck rails and door frames every few weeks in spring.