ECOLOGISTS have admitted defeat in their battle to eradicate a potentially dangerous moth from Hounslow, Richmond and surrounding areas.
Oak processionary moths, whose caterpillars have toxic hairs which can cause a painful rash and breathing problems in humans, have become established in west London in recent years.
The number of nests discovered in the area tripled from 700 in 2007 to 2100 last year, though most were destroyed before the moths hatched.
Rather than trying to eradicate them, the Forestry Commission has this year decided to contain them within a 'core outbreak zone'.
It will now be up to local councils withing this area, which also encompasses the boroughs of Brent, Ealing and Hammersmith & Fulham, to manage the pest.
The commission will continue to monitor moth populations in the area and will require any infestations on trees within a six-mile 'buffer zone' to be destroyed.
The moths, which can strip oak trees of their leaves, are native to southern Europe but have spread north in recent years.
Roddie Burgess, Head of the Forestry Commission's Plant Health Service, said: "We fully understand that local people and organisations will be very disappointed we are no longer pursuing a policy of eradicating oak processionary moths from West London.
"However, ministers have accepted scientists' advice that it is no longer practicable to do so, and have asked us to move to a policy of containment and management."