Oak processionary moth

The oak processionary moth (OPM) (Thaumetopoea processionea) was accidentally introduced into England in 2005. It lives on oak trees and poses a risk to human and animal health. It is present in the South East of England and in Elmbridge.

Health risks

It's important not to come into contact with OPM caterpillars, hairs or nests as their tiny hairs can cause skin rashes and less frequently eye and throat irritations and breathing difficulties in people and animals. Pets must be kept away from the nests and caterpillars.

May to July is the greatest risk period when the caterpillars are most numerous.

If you come into contact with the larvae or caterpillars by accident, follow the health advice about dealing with caterpillar hairs on NHS: Inset bites and stings - treatment. If you have an itching skin rash, conjunctivitis or other symptoms, contact your GP or call NHS 111.

What to do if you spot OPMs

If you think you've seen any processionary nests or caterpillars, first make sure you have correctly identified the species:

• see Forest Research: oak processionary moth 
• watch this short video - oak processionary moth: YouTube    

Reporting oak processionary moth (OPM) sightings

How to report sightings depends on who owns or manages the land: 

OPM on highways trees

Report to Surrey County Council  or email contact.centre@surreycc.gov.uk. 

OPM on a council-owned tree 

Report it to us by email at opm@elmbridge.gov.uk or call 01372 474825 or 01372 474579.

There is no single solution to managing OPM. We can't respond to all reports but rest assured we are following the process below with each reporting.

When risk assessing each site, we:

• look at each nest according to its location, and the risk to residents and pay particular attention to densely populated areas and the proximity to vulnerable individuals, for example, children, infants and elderly 
• control high risk areas by spraying (spring) or removing nests manually (from mid-June to August), where appropriate, and manage low risk areas through on-site information

OPM on land managed by PA Housing 

Report to PA Housing.

OPM on privately owned land

It is the responsibility of the land owner to look at individual trees and decide what is the appropriate management needed. We are unable to visit privately owned areas due to the scale and scope of the problem across the borough.

If you see oak processionary moths on privately owned land report them online using the Forest Research: Tree Alert. 

If you can't use Tree Alert, call 0300 067 442 or email opm@forestrycommission.gov.uk.

More information

• DEFRA's OPM resource Hub
• The Forestry Commission's management approach about infected trees
• Arboricultural Association 
• Forest Research: Manual for owners of oak trees.

For more information, email us at opm@elmbridge.gov.uk or call 01372 474579.