Oak Processionary Moths

OPM Nest Removal

You may have noticed some of our oak trees on the Green have been fenced off. This is due to oak processionary moths. The Oak Processionary Moth (OPM) is a quarantine pest and is under official control and must be reported. Although any tree can be infected they prefer mature oak trees. The moths are becoming more common.

Why does it matter to me?

OPM caterpillars and nests contain hairs which cause itchy rashes, eye and throat irritations and can cause breathing difficulties in people and animals. The caterpillars can shed hairs when they are disturbed. The nests and the caterpillars should not be touched. The greatest risk is between May to July when the caterpillars are most active.

What do they look like?

The nests are web like structure and are located on the boughs and branches of predominantly oak trees. The hairy caterpillars process in formation when they are moving, hence their name.

What action have the Parish Council taken?

We have had our oak trees reviewed by tree professionals. This years nests have been removed. The Forestry Commission has determined Writtle is located in the buffer zone. Currently they are actively treating sites in the buffer zone by spraying trees. We have reported the trees we can see have nests to the Forestry Commission and the trees will be sprayed in the spring. We will, as a precaution, relocate the two benches from under the large oak tree on the Green.

What action do I need to take?

Be vigilant. If you have large oak trees in your garden check them. If you spot a nest report it on Tree Alert – https://treealert.forestresearch.gov.uk/. Please do not touch the nests or caterpillars. If you or your pet comes into contact with them, please seek medical advice. The Forestry Commission have produced a useful leaflet with further information – https://assets.publishing.service.gov.uk/media/6278d2a98fa8f5206c75d3ed/FC_OPMoth_Leaflet.pdf