Experts are trying to rid Hollow Ponds of an invasive species of moth, which can strip an oak tree bare of its leaves.

Forestry Commission inspectors and Epping Forest officers discovered two Oak Processionary Moth (OPM) nests in the wooded area, near Leytonstone, last week.

The moth is an invasive species, native of southern Europe, where local environmental factors and predators keep its populations in check.

However, aided by the trade in live plants, it has become established as far north as the Netherlands and northern Germany. It was thought to have been first accidentally introduced to Britain in 2006.

Philip Woodhouse, chairman of the City of London Corporation’s Epping Forest Management Committee said: “OPM caterpillars damage oak trees by feeding on the leaves.

“In large numbers they can strip whole trees bare, weakening the trees and making them vulnerable to other threats such as drought and disease.

“We are working closely with the Forestry Commission and specialist contractors who will be undertaking a targeted treatment to control the caterpillars.

“This will remove the pest from the site and ensure that we protect other trees.”

The nests and the surrounding trees within a 50 metre area will be sprayed with a natural pesticide, which will control any caterpillar larvae that may be present.

The City of London Corporation says the treatment involves a natural agent that targets the caterpillars specifically, has minimal effects on other species and is not known to harm people or pets.

OPM caterpillars are most easily recognised by their distinctive habit of moving about in late spring and early summer in nose-to-tail processions, from which they derive their name.

The species almost exclusively lives in and feeds on oak trees.

Caterpillars have tiny hairs which can cause skin and eye irritations, sore throats and breathing difficulties in people and animals who come into contact with them.

Anyone who sees the caterpillars in any area of Epping Forest is asked to call forest staff on: 0208 532 1010 and to report the sighting to the Forestry Commission at: forestry.gov.uk/treealert.