Oak processionary moth: Tougher action needed to stop tree-killing insect in UK

Seven years of concerted action to slow the spread of oak processionary moth have failed to stop its consistent outward expansion from London


16 December 2021

oak processionary moth

Caterpillars of the oak processionary moth (Thaumetopoea processionea) on a tree trunk in Germany


Tougher action will be needed to stop a caterpillar threatening England’s oak trees from continuing to spread across the country, say researchers who found efforts to control the pest have failed to slow its steady growth.

The oak processionary moth (Thaumetopoea processionea) – or OPM – has spread as far as the M25 motorway around London, and occasionally even further afield, since it was accidentally imported to south-west London and detected in 2006. 

The invasive species’ caterpillars eat …