A coordinated response to the oak processionary moth outbreak

1st May, 2020

Oak Processionary Moth is an insect pest of oak, our most common broadleaved tree. The caterpillars feed on oak leaves and can increase a tree’s vulnerability to attack by other pests and diseases, as well as harsh environmental conditions. OPM is established in most of Greater London and some surrounding counties, but thanks to a robust government programme in place and national measures, the rest of the UK is designated as a Protected Zone.

In response to these findings, the Plant Health Service looked at oak tree imports into the country and have since traced over 2000 consignments of oak from the Netherlands, Germany and Belgium. To ensure vigilance, Government reached out to the trade including landscapers and nurseries, asking those who had planted or imported larger oaks from the continent to urgently check their trees.

Thanks to a swift and coordinated response, oak processionary moth was intercepted at over 70 planting sites in the UK Protected Zone. All infested trees and material were rapidly destroyed to eradicate the pest.

Professor Nicola Spence, Defra Chief Plant Health Officer, said:

“Since 2012 we have invested more than £37 million in tree health research, including a dedicated programme of research and development on oak.

“We will continue to work with local authorities and land managers to tackle OPM with a control programme of surveillance and treatment.”

If you suspect OPM, you should not attempt to destroy or move infected material yourself as the nests and caterpillars can pose some risks to human health. For more on how to identify OPM, visit the Forestry Research website.