Woodland Trust

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Leaf miner mothRich Andrews. ourweboflife.org.uk

What is it?

  • Cameraria ohridella, commonly know as horse chestnut leaf miner, was originally found on horse chestnut trees in London

  • The larvae of this tiny moth forms burrows within the leaf tissue, with heavy infestations resulting in leaf browning and drying and, over time, leaf death

  • The leaf miner was first observed in Macedonia, northern Greece, in 1985 before appearing unexpectedly in Austria in 1989

  • Since then it has spread throughout central and Eastern Europe

  • It was first found in Great Britain in 2002 in the London Borough of Wimbledon

  • Over the last few years its range has expanded north, travelling between 40 and 60 km annually; the speed of this suggesting that some moths have been carried inside vehicles

       More information..

Advice for recording leaf tint etc. with us

There is no current evidence that damage by the moth leads to a decline in tree health or results in death, although it is likely to have an effect on the timings of autumn events like fruiting, leaf tint and fall. 

We advise that if your tree is infected by leaf miner then continue to record as normal and we will take the widespread infestation into account when we look at everyone’s results.

How to report that your local trees are infested

If you have spotted the leaf miner in a new part of the UK please send in your sighting to Forest Research (webpage includes current distribution map).

Alternatively, as we mentioned in our September news, The Universities of Hull and Bristol want to hear from you, whether you have had infestations in your area for years or even if your trees are not yet infested.

Infected tree management advice