Conker Tree Science: LeafWatch. Help scientists track the spread of the horse-chestnut leaf miner moth with this simple, intuitive app. What is happening to Britain’s horse-chestnut trees? Since 2002 Britain’s conker trees have been under attack from a non-native moth – and you can help scientists monitor what’s happening. The LeafWatch app shows you how to identify affected trees and enables you to submit your geo-located leaf photos. This data will show our scientists where the moth is present within the UK today. Your reports will contribute to the Conker Tree Science research project. Visit us at http://www.conkertreescience.org.uk/.