What is Oak processionary moth?

Oak Processionary Moth (OPM) gets its name from the distinctive processing behaviour of the caterpillars because they tend to move in nose-to-tail lines.

The caterpillars of these moths feed on oak leaves leading to severe loss of foliage which can weaken the trees and make them more vulnerable to other diseases. However, the main concern with this pest is the threat to human health because the caterpillar hairs can cause severe allergic reactions.


health precautions

The oak processionary caterpillars’ tiny hairs contain a toxin which can lead to itching skin lesions and, less commonly, sore throats, breathing difficulties or eye problems. This can happen if people touch the caterpillars or nests, or if the hairs are blown into contact by the wind

  • For this reason, avoid contact with the nests and caterpillars – and keep pets and livestock away from them too

  • The nest may persist for several years. Please treat these with the same caution as a live nest

  • Adults and children must see a doctor immediately if they have come into contact with OPM and begin to suffer symptoms

  • If pets or livestock come into contact, they should be removed from the area and a vet should be contacted.

how we can help

Down to Earth are familiar with the in-depth safety precautions required when dealing with the removal of OPM nests.

Removing and destroying nests between late June and early August is considered to be the most effective time during the lifecycle. By this time all of the larvae will have settled into the nest as pupae, and none of will be out on the foliage. It is therefore unlikely that any of the pupae will survive treatment to breed another generation.


Areas we cover

We cover most of the South East including Kent, Surrey, Sussex, London and Essex.