Ramorum disease of larch trees has been found in Cumbria for the first time.
The disease, which kills larch trees very quickly and is a recent arrival in Britain, has been confirmed in two woods in the Eskdale Valley in western Cumbria.
Larch trees produce large quantities of the spores that spread the disease, which can infect many species of trees and plants. The only available disease control treatment is to fell the trees, preferably before the next spore release, which current knowledge indicates occurs in the autumn.
The outbreak is the second in North West England after one in southern Lancashire, and only the third outbreak in England outside the South West, where the disease has caused the premature felling of hundreds of thousands of larch trees.
There have been findings of ramorum disease on other plants, such as rhododendron, near the affected woods. Investigations are continuing into other suspected sites identified by aerial surveys in northern England, and the Forestry Commission believes there is a possibility that more outbreaks will be found.
Ramorum disease is caused by Phytophthora ramorum, a fungus-like pathogen that is particularly serious in Japanese larch trees and rhododendron, both of which produce large numbers of infective spores.
The outbreak was first suspected during aerial surveys to look for signs of the disease by the Forestry Commission, in conjunction with the Food & Environment Research Agency (Fera). These are continuing over large parts of Britain. Experts follow up with ground inspections and laboratory analysis of samples taken from trees showing possible symptoms of the disease. Other larch woodland in surrounding areas is inspected from the ground to check whether the disease is more widely present. Local woodland owners are being informed and given information about the disease and the measures for containing it.
