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Oak Processionary Moth (OPM)

Oak Processionnary Moth (OPM)Oak Processionary Moths (OPM) are a tree pest.                                   

Accidentally introduced to Britain and first reported at several locations in south-west London in 2006, there are now several confirmed breeding sites in Southern England.

OPM caterpillars feed on the leaves of many species of Oak and, in large numbers, can severely defoliate trees and leave them vulnerable to other pests and diseases.

OPM caterpillars also present a risk to human health.  Their tiny hairs contain a protein which can cause itchy skin rashes and, less frequently, eye and throat irritations and breathing difficulties in people and animals. The hairs can be blown on the wind or found in nests in or under infested trees.

The greatest risk period is May to July, but nests should always be avoided because they can contain thousands of shed hairs.

Further information is available from the Forestry Commission: OPM public information leaflet  

If you see OPM nests or caterpillars they must be reported:

Health advice is available from the “Insects that bite or sting” area of the NHS Choices website