Mission: alien moth survey

Survey trees in your area - anywhere in the UK - for invading alien moths

What are you looking for? The damage caused by the leaf-mining moth is often obvious, but it can be confused with other types of damage (see the photo below).

This mission ran from 2010 to 2013. We are currently setting up a new way of recording, which we will link to from this website site.

Conker Tree Science Leaf Watch logo

In 2011 we also produced a smartphone app (the LeafWatch app), although from 2014 onwards we can only offer very limited support for this app. It was one of the first apps of its kind (so now would need ot be updated to work efficiently), but we are keeping it on the App Store and Google Play for people's reference.

All you need is:

  • A few minutes at a horse-chesntut tree anywhere in the country.

Your mission in brief:

  • Find a horse chestnut tree (see here for help with tree identification).
  • Look at the leaves near the bottom of the tree: can you see whitish blotches, made by the alien moth?
  • Find out the nearest postcode or write down the location so you can find the tree on a map.
  • Use the detailed instructions to decide how badly affected your tree is. 
  • Submit the information to our database, even if your tree is not infected.

Download detailed instructions


Check out the identification of the alien moth damage. The damage labelled as 'not a leaf miner' is actually a fungus (called Guignardia) that was introduced by accident, but does not seem to do the trees any harm. It is most prevalent in autumn.



Moth hiding (photo: Grahame Madge)
The tiny moths are well camouflaged against bark
(photo: Grahame Madge)