The pathogen Phytophthora ramorum is responsible for 'sudden oak death' in the USA and 'sudden larch death' in the UK. In Europe, it is currently mainly present in nurseries on ornamental plants (such as rhododendron or camellia).

In France, it is a quarantine pest, subject to eradication as soon as a plant is infected. Despite this, it was found in 2018 on larch trees in Finistère.

In England, reports on chestnut trees are multiplying, showing that this species is a susceptible host.