Box Tree moth

Derby day

This year Saturday 7th June.

Traditionally the day for gardeners to trim their box bushes.

Box bushes (in the foreground) are ubiquitous in English gardens..

This year no trimming will be necessary here as almost all the box bushes we’ve grown for the past twenty-or-so years have been killed by the caterpillars of box tree moth.

Damage wrought by box tree moth caterpillars

Box Tree moth (Cydalima perspectalis) was first recorded here in the garden only last year. Suddenly a biblical plague of them sees bushes decimated and their adventurous caterpillars everywhere.

Box tree moth caterpillar

Here’s one who pupated in the kitchen!

The destruction of box bushes is truly devastating both for gardens and nature.
It has been used for hedging and topiary for centuries. It is a native tree but the majority of box grown in gardens are cuttings of cuttings of cuttings. The consequence of this constant cloning is that all our garden bushes are probably genetically identical. And due to this, there isn’t the capacity within the identical population to throw up variants that are resistant to the box tree moth.

So. just as Dutch elm disease swept through the entire population of our English elms which were cloned, the same is likely to happen to garden box bushes.

A variegated box in the garden has been slightly affected by the caterpillars but hasn’t been devastated yet. Perhaps there’s some resisitance within this strain? It is far too early to say.

In the meantime we must think again. The box bushes are being removed and burnt. Replacements of a different species will have to be found.

Our gardens will not be the same again.