Hounslow Council is advising people not to be alarmed by workers wearing protective clothing in parks and other sites around the borough.
The teams are trained tree experts drafted in to combat the spread of the Oak Processionary Moth which is harming trees and woodland across Europe.
The caterpillars feed on the foliage of many species, including English, Sessile and Turkey oaks, as well as hazel, beech, sweet chestnut and birch trees. The caterpillars derive their name from the fact that they feed together and move from tree to tree in long columns.
The experts are donning the suits to stop them inadvertently spreading the pests from one tree to the next and because the hairs on the caterpillars can irritate the skin.
Experts working for the Forestry Commission and Carillion, which manages Hounslow Council’s parks, have started to remove nests from infected trees in the borough.
People who spot the caterpillars or nests of the moth are asked to contact the Forestry Commission or the council if it is on council-owned land.
Councillor Ed Mayne, Hounslow Council’s Cabinet Member for Public Health and Leisure, said: “It is a shame that the moth has made its way to our parks but we are working with the Forestry Commission to control its spread. I ask people not to be alarmed by the experts’ presence as the moth does not present a serious threat to humans but please do report these caterpillars or their nests if you spot them.”