What should I do about a wasp nest?

Wasps are useful predators for most of the summer and a nuisance for a few weeks at the end of it, when the colony stops rearing brood and the adults go looking for sugar. Most nests genuinely do not need treating. The ones that do need treating are exactly the ones an amateur should not attempt, which is an unusually clean decision.

Safety

Step by step

1. Confirm it is wasps and not bees.Wasps are smooth, bright yellow and black, and fly with a purposeful darting movement. Honeybees are furrier and browner; bumblebees are large and fuzzy. Bees should be left alone or moved by a beekeeper, never treated.
2. Find where they are going in.Watch from a safe distance for a few minutes. A steady two-way traffic stream at a hole in the eaves, an airbrick, a soffit or a shed corner tells you where the nest is without going near it.
3. Ask whether it is genuinely in the way.A nest at high level away from doors, paths, washing lines and play areas can be left. The colony dies with the first hard frosts and the nest is never reused, so doing nothing is often the right answer.
4. Treat it as urgent if it is near people.Above a door, beside a window that gets opened, at head height by a path, in a child's play area, or inside the house. Those need dealing with promptly and professionally.
5. Do not use an aerosol on an established nest.A spray irritates the colony without reaching the nest interior, the alarm response brings hundreds of wasps out at once, and you cannot outrun them from the top of a ladder. This is how people end up seriously stung.
6. Never treat a nest in a loft or a cavity.You are in a confined space with one exit, wearing no protection, with a colony between you and the hatch. Professionals do this with a suit and specific equipment for exactly that reason.
7. Call a pest controller and say where the nest is.Height, access and whether it is inside determine what they bring. A BPCA or NPTA member, or your council's pest service, which often treats wasp nests at a modest fixed fee.
8. Keep people and pets away until it is done.Close the windows on that side, keep children and dogs indoors, and mark the area. Most stings happen because somebody walked into the flight line without knowing.
9. Leave the nest alone after treatment.Wasps returning from foraging come back for a day or two. Do not block the entrance immediately — it stops the treatment reaching returning workers. Once activity has stopped completely, seal the gap so nothing nests there next year.
10. Proof the entry point in autumn.The nest itself is not reused, but a good site is often re-chosen. Once the colony is dead, mesh or seal the gap in the soffit, the airbrick or the shed.

Tips

• A nest found in spring the size of a golf ball, with a single queen, is the one case where early removal is straightforward — and it is still worth checking whether it is somewhere that matters.
• Late-season wasps at a picnic are foragers from a nest that may be a long way away. Dealing with a nest you cannot find is not the answer; covering food and using a diversion feeder away from the table is.
• If anyone in the household carries adrenaline for a sting allergy, treat any nest near the house as needing prompt professional removal.

Common mistakes

• Spraying a nest at dusk from a ladder — Dusk is when the whole colony is at home. The ladder removes your ability to retreat, and disturbed wasps sting repeatedly. This combination causes most serious incidents.
• Blocking the entrance hole to trap them inside — Wasps chew through plaster, insulation and plasterboard to escape, and frequently emerge inside the house instead. It turns an outdoor nest into an indoor one.

If it doesn't work

Questions people ask