West London Box Tree Caterpillar Invasion – Updated 11/8/17
On returning home from a week away, the EBTS UK Chairman found unwanted guests chomping through his box hedging in both the front and back gardens. Looking at other front gardens in the area, with boxwood in them, there appears to be a significant outbreak of box moth and it’s caterpillars in the area.
Spraying with Bayer Provado Ultimate Bug Killer didn’t seem to kill the caterpillars, they were still eating away at the bushes 2 days later.
Topbuxus XenTari (a biological insecticide) has been ordered to see if this works better and will be sprayed as soon as it arrives. Also a pheromone trap has been ordered to try and trap the adult male moths before they breed with the females.
Note: Currently Bt based products (like XenTari) are not registered for domestic use in the UK, they are available for use by professionals.
UPDATE 31/07/17
The XenTari was used and the caterpillars stopped eating within 1 hour and died within a couple of days without eating any further leaves. The box hedge is now growing new leaves and the damage is slowly fading away. It has also been used, with similarly good effect, on 3 other West London gardens that had even worse caterpillar infections.
UPDATE 21/07/17
The ‘Bayer BuxaTrap‘ pheromone traps were installed and within 24hrs there was a moth in the front garden trap and the following day a further 2 moths in the back garden trap.
Observations
Although anecdotal, there have been a larger number of moths spotted this year than in previous years in the West London area. It seems, it wasn’t just cloths moths, that the residents of West London should have been worrying about. Other areas have also been badly affected, such as Southfields & Balham in South London.
08/08/17 Two reports today of box tree caterpillars in Islington, London.
10/08/17 Epping, Essex box hedging and topiary in both front & back gardens found with relatively early caterpillar damage – other gardens in the area also appear to be infected.
RHS Tracking of Box Tree Moths
The RHS are trying to track the spread of Box Tree Moth across the country so it would help them if you were to let them know if it has attacked your box plants.
In the meantime the Chairman will be out looking for and squashing any caterpillars he finds.