Anyone who has spent any time scrutinising a bramble bush at this time of year will be familiar with the snake-like trace on the leaf surface. These labyrinth squiggles are the tunnels of the serpentine leaf miner caterpillar, which eats the leaf from within the leaf, before pupating and emerging as a tiny moth.


The serpentine leaf miner is a native moth, which has successfully co-existed with bramble for millennia, anyone clearing an overgrown garden will testify to how pioneering the plant is! However, a new leaf miner has arrived on our shores and scientists at the University of Bristol are appealing for help in tracking its spread.

The Horse Chestnut leaf miner is a rather gorgeous moth which was first recorded in London as recently as 2002. It may be attractive, but it is capable of causing considerable damage to conker trees as its mines within the leaf, are large and are so profuse that they severely restrict the tree’s ability to photosynthesize.

As the photo shows, the caterpillars hatch from the eggs and eat the spongy layer of the leaf, known as the mesophyl, safely tucked away from harm, protected by the upper and lower leaf membranes. This larval safety means that the moth has been able to spread at an incredible rate, from the first records from the Capital in 2002, the moth is now known from Cornwall to Kent; Hampshire to the Midlands.

The Universities of Bristol and Hull have teamed up to investigate the movement of this new species and the scientists have set us a challenge. Citizen science is all the rage at the moment, but this time it’s gone digital!

If you have a smart phone, be it iPhone or Android, you can download a free app (as I have) which will help you to submit recordings of horse chestnut miners as and when you find them. The app will allow you to snap a photo of the leaf and send it to the project, complete with all the details the boffins need. What a fabulous use of technology!

This initiative is causing quite a stir. My attention to the project came via Stephen Fry, albeit on Twitter! Twitter is fast becoming the preferred means of sharing information between interested individuals, as you can tailor your feed to only show you people or organisations you are interested in. I was logged in to my account when a link popped up from Mr Fry to the University of Brisol website, I duly opened the page, read the report and downloaded the app. Hey-presto, another leaf watcher enrolled with, hopefully, a few more on the way!

I’ll retweet the link on the East Devon District Council twitter account @WildEastDevon so if you follow us, you’ll see what I am talking about in due course.

The app can be downloaded from and Stephen Fry can be found on Twitter at @stephenfry - give him a follow and tell him @TheTiercel says "Hi!"