How do I know there is a nest?

From late spring, a queen that has survived the winter starts a nest the size of a golf ball. By high summer the colony can hold thousands of workers. The sign most people notice is a steady flow of wasps to and from a single point: a gap under the roof tiles, a hole in the soffit or fascia, an airbrick, a loft vent, a cavity wall, a shed, a bird box or a hole in the lawn. The nest itself is often hidden, so it is the traffic you see, not the structure.

Inside a loft or shed the nest looks like a papery grey ball, made from chewed wood. Do not poke it, tap the wall around it or shine a torch on it for long, because disturbed wasps defend the nest together.

Is it wasps, hornets or bees?

It matters, because the answer decides who you call.

Common and German wasps are bright yellow and black with a narrow waist and little hair. They are the ones at your picnic in August.
European hornets are larger, with brown and yellow markings. They are a native species and less aggressive than their size suggests, but a nest beside a door still needs dealing with.
Honey bees are smaller, browner and fuzzier. They are not treated as pests. A swarm hanging from a branch or clustered on a wall is usually resting on its way to a new home. Contact a local beekeeper or the British Beekeepers Association, which keeps a list of swarm collectors, rather than a pest controller.
Bumblebees nest in small numbers in compost, bird boxes and under sheds, and die off at the end of summer. They are best left alone.
Solitary bees, such as the masonry bees that use old mortar, do not form colonies and are harmless to leave.

If you can take a photo from a safe distance, the pest controller can usually identify the insect from it.

Will the nest go away on its own?

Yes, eventually. Wasp colonies are annual. The workers die off with the first frosts, and the new queens leave to hibernate elsewhere. A nest is never reused, although a new queen may start one nearby the following year. So a nest found in October in a part of the loft you never use can be left. A nest found in June beside the back door, with a toddler in the house or someone who reacts badly to stings, is a different decision.

What does the treatment involve?

A pest controller normally applies an insecticidal dust or spray at the entrance of the nest, from outside where possible, using a lance to reach soffits and eaves. The returning workers carry it into the nest and the colony dies off over the following day or two. The nest itself is usually left in place, since taking it out of a loft or wall can do more damage than the wasps ever did, and an empty nest will not be reoccupied. If you want it removed once dead, say so when you enquire.

Keep windows closed and people and pets away from the treated entrance for as long as the controller advises, because wasps can be agitated for a few hours afterwards.

Should I try a shop-bought spray?

Aerosol products for wasp nests exist, but they are for small, exposed and easily reached nests. Treating a nest inside a roof, up a ladder, at dusk, with no protective clothing, is how many sting accidents happen. If the nest is high up, inside a structure, or anyone in the household reacts badly to stings, leave it to someone with the equipment.

What if someone is stung?

Most stings are painful for a few hours and need nothing more than a cold compress and an antihistamine from a pharmacy. Call 999 if the person has swelling of the face or mouth, difficulty breathing, a fast heartbeat, dizziness or has collapsed, since these can be signs of a severe allergic reaction. Anyone who has been prescribed an adrenaline auto-injector should use it as they have been taught.

Where do nests turn up around Enfield and Barnet?

The 1930s semis that make up so much of both boroughs have the classic wasp entry points: timber soffits with gaps, loft vents, and tile hanging on gables. Wasps also nest in the ground on railway embankments, in the banks of the Dollis Brook, Pymmes Brook and the New River, in allotment sheds and under decking. Terraced streets in Edmonton and Finchley often have nests in shared roof spaces, so it is worth telling the neighbour, because the entrance may be on their side.

What should I include in my enquiry?

where the wasps are going in and out, as precisely as you can
how high up it is and whether it can be reached from the ground or the garden
whether it is in a loft, a wall, a shed, the ground or a tree
whether anyone in the home reacts badly to stings
your postcode and a phone number you answer

What happens after I send it?

If you consent, the enquiry goes to one local pest controller who covers your postcode, if one does. They contact you to confirm what you have described and talk through a visit. We do not treat nests ourselves and cannot say how soon anyone will be able to come. If nobody covers your area, we say so and share nothing.

Who you will hear from

We pass your enquiry to one local pest controller, if one covers your postcode. It is never sent to a list of companies. If nobody covers your postcode, we will tell you and will not pass your details on.