Ramorum disease of larch trees has been found in Derbyshire’s Peak District.
The Forestry Commission has confirmed the disease in Japanese larch trees in a small woodland between Bakewell and Matlock, 80 miles from the nearest previously known outbreak in larch.
The disease, caused by the Phytophthora ramorum pathogen, can kill larch trees within a year of symptoms first being detectable. Japanese larch needles also produce huge quantities of the spores that spread the disease, so the trees must be felled quickly to limit its spread.
Previously the pathogen has been recorded on other plants such as rhododendron and bilberry in South Wales, South West England and parts of the Midlands and North West, including Derbyshire. However on larch trees it has been confined until now mostly to South Wales and South West England, with single isolated sites in central and northern Wales and western Scotland, and a small number in Ireland and Northern Ireland.
The Peak District outbreak on larch was first noticed during extensive aerial surveys of southern and western Britain and central England to spot possible signs of the disease. Ben Jones, the Forestry Commission’s phytophthora programme manager, reported,
“It’s too early to predict the full implications of this find so far from any other known infected larch woodland. There have been infected rhododendron shrubs in the area, so we are double-checking nearby woodlands.
“Local stakeholders will be informed and local meetings will be held to raise awareness of the disease and the measures that are required for containment.
“Almost all the other sites that we are most suspicious of at the moment are either close to or contiguous with existing infection sites that were identified in 2009 and 2010.
“We are also encouraged that the area of woodland identified from the air that needs follow-up checks is down on last year. However, we cannot afford to be complacent because the dry spring weather might have delayed the onset of symptoms in some areas, so we will remain alert for symptoms emerging for the remainder of the year.”
Meanwhile Dr John Morgan, head of the Forestry Commission’s Plant Health Service, has paid tribute to woodland owners who have co-operated with the ramorum disease management programme.
“The past two years have been a difficult time for the forestry community, especially those woodland owners who have suffered heart-breaking losses of valuable trees. Without their prompt co-operation, we would almost certainly be in a much worse situation, with more infected woodland.
“I would therefore like to thank them, and everyone else who has responded so well to this challenge, from the contractors, hauliers and processing companies to the scientists who have worked tirelessly to give us answers, and the Cambridge University modellers who have produced the risk models that guide our management and surveillance strategies.”
Since 2009 a contingency plan has been implemented to limit the spread of the disease while minimising the impact on forest industries and visitors. Among achievements to date are:
licensing and authorisation systems to enable hauliers and wood-processing plants to transport and process logs from infected woodland, subject to ‘biosecurity’ precautions to prevent disease spread during movement and processing;
the establishment of protocols setting out measures that can prevent accidental spread of the disease on footwear, clothing, vehicles, machinery, tools, equipment or pets;
the establishment of a group to manage the increased flow of larch timber on to the market in a way that minimises market distortion;
the provision of grants in England and Wales to help affected woodland owners comply with requirements to fell or clear infected trees. The grants are provided from Defra’s Phytophthora Programme, administered by the Food & Environment Research Agency (Fera);
the provision of enhanced restocking (replanting) grants to help affected owners in England replant trees on sites where they have been required to fell infected trees; and
significant advances in scientific understanding of the disease gained from intensive research by scientists at the Forestry Commission’s Forest Research agency and Fera.
Dr Morgan added, “We urge everyone to remain vigilant for signs of ramorum disease, not just in larch trees, but also in other vulnerable plants, particularly rhododendron and bilberry. Anyone who suspects they have seen its symptoms should report it to us without delay.”
Detailed information about P. ramorum is available from the Forestry Commission’s website at www.forestry.gov.uk/pramorum.