View this email in your browser

Issue 3, May 2021

Programme updates will be published regularly throughout the OPM season, covering key stages such as caterpillar emergence, as well as information and surveillance. Please share with your contacts where appropriate.
In light of coronavirus (COVID-19), Defra and the Forestry Commission have carried out a review of critical functions and concluded that the control and surveillance of OPM should continue into 2021. All OPM work will take place in line with government measures on COVID-19. We are constantly reviewing official guidance in relation to the coronavirus outbreak and if this situation changes, plans may have to be adjusted.
Visit our website

Spray programme

Oak processionary moth caterpillars were first spotted emerging from their egg plaques in London on the 14th of April – later than in 2020. A big thank you to the Royal Parks for monitoring egg hatch.

Our contractors began treating known affected oak trees from the 19th April. From surveying and monitoring activity over the past two years, we have identified more than 2000 sites (areas with one or more trees) for treatment in the Control Zone. Over 450 of the identified sites due for treatment have had their first sprays and we expect this number to rise rapidly within the next few weeks.  
Other caterpillar reports

We are beginning to receive reports of native caterpillars that are mistaken for OPM. Brown-tail moth is frequently confused for OPM and need not be reported to the Forestry Commission. Now is a good time to familiarise yourself with caterpillar species that could be mistaken for OPM. Please see the Forest Research webpage and poster to help you identify similar looking species.  

Training events reminder

A reminder that we are still taking places on our virtual OPM training sessions. Events will be held via Microsoft Teams on the 2nd and 4th of June between 11-12:30pm. Register your interest here.

Reporting OPM

We expect towards the end of May we will start receiving further reports of OPM, when the caterpillars will be large enough to be seen by the public. It is at this time when they will be on the move and also developing the hairs which can cause irritation. This is a reminder to not approach or touch the caterpillars but please do report all OPM sightings to us via the online portal Tree Alert  Alternatively, you can send in your reports to

We anticipate that partners in the Core Zone such as local authorities and other managers of large landholdings are also undertaking their operations about now.

And finally...

Please continue to report OPM sightings via the contact information below.

If you’re new to OPM, please note that we have an OPM manual on our website with guidance on surveillance, identification and managing OPM. You can find it at

The Forestry Commission has a suite of communication resources which partners are welcome to use. PDF versions of posters, leaflets and banners are available under ‘Further information resources’ at the bottom of the OPM webpage at

Please send us information on your OPM activity so that we can provide up-to-date and comprehensive OPM reports, including developments outside Defra/FC-funded work.  Email your updates to


Share Share
Tweet Tweet
Forward Forward
Copyright © 2021 Forestry Commission, All rights reserved.

Our mailing address is:

Our contact number is:
0300 067 4442

Click to unsubscribe or contact us using our email address above. 

This email was sent to <<Email Address>>
why did I get this?    unsubscribe from this list    update subscription preferences
Forestry Commission · Bucks Horn Oak · Farnham · Surrey, GU104LS · United Kingdom