Box Tree Caterpillar Infestation in Thame

The Royal Horticultural Society (RHS) has issued a warning over box caterpillars stripping leaves from hedges.

Box tree caterpillars are the larvae of a moth that feeds on box plants. The species is native to East Asia but has been present in southern parts of the UK since 2014. The box caterpillar has yellow and black stripes along its body with a black head. Its presence can be noticed by defoliation or webbing on box plants.

In recent weeks, there have been reports of an infestation in parts of Thame, affecting box hedges, trees, and bushes. Box trees and large hedges have been seriously damaged around the area of Priest End and Aylesbury Road.

The RHS advocates for non-pesticide methods of removal, which include removing caterpillars by hand or setting pheromone traps.

Pheromone traps
Pheromone traps feature a synthetic pheromone that mimics the one produced by the female box tree moth. The male moths are then attracted to the pheromone and become stuck inside the trap, disrupting the breeding cycle. The traps need to be replaced frequently and are unlikely to catch all of the male moths in your garden. However they are a useful indicator of the presence of box tree moth so you can take prompt action.

Be vigilant
Box tree caterpillars can be hard to spot as they conceal themselves well. Therefore check your plants regularly, looking deep inside the plant and around its base.