Asian Box Tree Caterpillars

Hi all. I don't know if anyone else is having a crisis with these foreign invaders but we are currently watching our beautiful box hedges being rapidly destroyed by these very hungry caterpillars. The hedges have gone from beautiful green to brown in the matter of days. I noticed my neighbours are also having the same problem. They are almost impossible to stop and I have tried powerhosing the hedges with some success (it removed most of them) but within 12 hours they were back again with a vengeance. It is heartbreaking to watch and couldn't have come at a worse time as we are trying to sell our house. I would be interested to hear if anyone has encountered these pests and had any luck in saving their hedges. I have read that the moths that these caterpillars turn into have managed to reach London by flying over the channel. Even Monty Don has watched his beautiful garden hedges being destroyed. This could be the end for our lovely sculpted hedges.
one of our hedges destroyed in a week


I'm sorry to say but as with all invasions, after the event is too late. Please read my posts regarding chenilles processionnaires (not these critters).

It is not possible to treat with chemicals when bees are active. Bacillus thuringiensis var kurstaki (Btk) is a biological insecticide specifically for caterpillars, professional use only, can be used on caterpillars between September and December. Eco pièges won't work and are not necessary as these caterpillars do not constitute a health hazard.

Summer months install pheromone traps, which emit a female sex pheromone and attract the males to a frustrating demise. In the autumn, install bird boxes so the birds get used to them and hopefully rear their young, a great tit can scoff up to 500 caterpillars a day.

So, unfortunately there is not a lot you can do apart from jet washing your bushes or making them unattractive to eat, without killing the bush or don't go getting chemicals from your farmer!

Good luck.


Hi Rob, I had the processional ones as well but burned them. Seems we're plagued with misfortune this year. Something needs to be done to stop these caterpillars or it will be like locusts and wheat fields. Europe and the UK could lose box hedges forever. Horrible thought. Regards, Ralph

They've finished off ours as well -- 64360 Monein