Chestnut leaf miner

Until a few years ago, horse chestnut trees in Britain had lovely glossy leaves that stayed healthy and green right through the summer months, turning brown and falling in the autumn.

Damaged chestnut leaves

But then the chestnut leaf miner came to Britain and everything changed. The leaf miner is a small moth, only 5 mm long.

The adult females lay their eggs on the chestnut leaves and the young caterpillars burrow inside and feed on the sap from a leaf vein. The chestnut leaves develop dead, brown patches as a result.

The caterpillars pupate and mature moths emerge and lay more eggs. There are between three and five generations each summer and the leaves become severely damaged.

When the leaves fall in the autumn, the pupae hibernate through the winter and emerge as adults the following year to repeat the process.

It's a real shame that the trees are spoiled in this way. The moth originated in Macedonia but has spread rapidly throughout most of Europe in the last twenty years.

(If you liked this you might also like Journeys of heart and mind and Quote me on this.)