A coordinated response to the oak processionary moth outbreak
1st May, 2020
Oak Processionary Moth (OPM) 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.
Oak Processionary Moth 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.
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.
“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.”
Oak processionary moth (Thaumetopoea processionea)
The caterpillars (larvae) of oak processionary moth (OPM) are pests of oak trees (trees in the Quercus genus), and a hazard to human and animal health. OPM was first accidentally introduced to England in 2005, and is subject to a government-led programme of survey and control to minimise its population, spread and impacts.
Additional information can be found on the Forestry Commission website here:
Forest Research often receive reports of caterpillars which are not OPM, and the following page and poster have guidance on distinguishing between OPM caterpillars and those of other species:
How to identify Oak Processionary Moth in woodlands, parks and gardens
