Principle species colonised.
Typically Horse Chestnut.
Identification.
The larvae of the moth Cameraria ohridella are known as horse chestnut leaf miners. The adult moths are very little, measuring just 4 to 5 mm. They have a deep brown hue with black-edged chevrons of brilliant white.
The mature female deposits up to 180 eggs on freshly opened leaves in the early summer. The hatched larvae go through multiple growth stages, growing from 0.5 mm to 3.5 mm while feeding on the leaves. After pupating, the larvae might spend the winter in the leaf litter until emerging as adults in the early spring to lay their eggs on the new leaves of that year.
Type of symptoms.
Among the symptoms are:
- Traces that the feeding larvae leave in the leaves.
- Brown, crisp, and dry leaves.
- The tree may be entirely barren by autumn due to premature leaf loss.
The threat to host.
When horse chestnut leaf miner infestations accumulate, all of the tree’s leaves may turn brown and shrivel because the larvae consume all of the leaf substance. The tree may deteriorate after years of persistent infection.
Impact / Effect / Significance
The horse chestnut leaf miner has so far expanded from England to Wales and, more recently, to the central belt of Scotland.
