Horse-chestnut leaf miner
First recorded in the Balkans in the 1980s, this tiny moth spread across Europe at up to 70 kilometres a year, reaching the far northwest of the continent by 2002.
| Where | Parks, streets and gardens with horse-chestnut |
|---|---|
| Size | 8 to 10 mm wingspan |
| When | June to October |
The Horse-chestnut leaf miner is a tiny moth, roughly 8 to 10 mm across the wings, colored dark reddish brown with fine silvery streaks. Its caterpillars tunnel inside horse-chestnut leaves, producing pale blotches that turn brown and can cover much of a tree's canopy by late summer.
Two to three generations develop each year between spring and autumn, with pupae overwintering in fallen leaf litter. Larvae feed almost exclusively on horse-chestnut, occasionally straying onto sycamore or other maples growing nearby.
Traits
Habitat
Towns
Colour
Brown
Active
Day
To people
Not known to affect people directly, though heavy infestations can make host trees look scorched by late summer.
Activity through the year
Often confused with
A very similar 8 to 10 mm wingspan, but its caterpillars mine only London plane leaves and form a single large tent-shaped mine, unlike the many small blotch mines the Horse-chestnut leaf miner leaves on chestnut.
Questions
Is the Horse-chestnut leaf miner dangerous to people?
Not known to affect people directly, though heavy infestations can make host trees look scorched by late summer.
When can you see the Horse-chestnut leaf miner?
The Horse-chestnut leaf miner can be seen from June to October, by day.
Plate retouched from a photo by Gubin Olexander, CC BY 4.0, Wikimedia Commons Licence
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Butterflies and moths›Leaf-blotch miner moths›Cameraria
Last updated 2026-09-26. Every entry is checked against published sources.