Ref. TPC-N04

Found a wasp nest? What to do (and what not to)

Case note · Wasps

A steady stream of wasps flying in and out of one spot, such as a gap in the eaves, an air brick or a hole in the ground, usually means a nest. Keep people and pets away, don't block the entrance or try to knock it down, and get it treated if it's near doors, windows or play areas.

§ 01

Signs of a nest

Watch the area on a warm day. If wasps are flying in a fairly straight line to and from the same spot, there is almost certainly a nest there. Common places are roof eaves and soffits, lofts, sheds, wall cavities, air bricks, hedges and holes in the ground. In a loft, nests look like a grey, papery ball.

§ 02

Does it need treating?

A nest at the far end of a large garden that nobody goes near may be left alone, as wasp colonies die off in autumn and old nests are not reused. A nest near doors, windows, patios, bins, play areas or in a loft is a different matter, particularly if anyone in the household is allergic to stings.

§ 03

What not to do

  • Don't block or fill the entrance. The wasps will look for another way out, sometimes through a ceiling into the house.
  • Don't knock the nest down, spray it with water or try to burn it.
  • Don't stand in the flight path or swat at wasps near the nest; disturbed wasps release a scent that alerts the rest of the colony.

§ 04

Wasps or bees?

Wasps are smooth, bright yellow and black with a narrow waist. Honey bees are smaller, browner and hairier, and bumblebees are large, round and furry. We don't treat honey bees; if you have a swarm, a local beekeeping association can often collect it. Bumblebee nests are usually small and short-lived, and can normally be left alone.

§ 05

Keeping safe until it's treated

  • Keep children and pets away from the area and close nearby windows.
  • Keep sweet drinks and food covered outdoors.
  • If someone is stung and has trouble breathing, swelling of the face or throat, or feels faint, call 999.

— Field diagram

Where to check for wasps

Fig. 4a — Common places to find wasps in and around a home
  1. LoftLarge nests hanging from rafters
  2. Eaves & rooflineUnder roof tiles, soffits and fascias
  3. Walls & cavitiesAir bricks and gaps in brickwork
  4. Garden & shedsSheds, hedges, bird boxes and the ground

Seasonal activity

PestJanFebMarAprMayJunJulAugSepOctNovDec
WaspsJanuary: InactiveFebruary: InactiveMarch: InactiveApril: LowMay: LowJune: ModerateJuly: PeakAugust: PeakSeptember: PeakOctober: LowNovember: InactiveDecember: Inactive
Fig. 4b — When wasps are most active in Essex