Exmoor National Park Authority is to fell approximately 30 Japanese larch trees in Hadborough

Exmoor National Park Authority is to fell approximately 30 Japanese larch trees in Hadborough Plantation where a serious plant infection Phytophthora ramorum commonly known as ramorum blight has been discovered. The Forestry Commission have issued a Plant Health (Forestry) Order to fell all the affected trees thus removing a potential area of infection.

Graeme McVittie, Woodlands Officer at Exmoor National Park Authority said: “The news that the disease was in the Hadborough Plantation is a terrible shock, but we are acting responsibly and decisively to try and prevent it from spreading to more valuable woodlands on Exmoor. For the time being we will fell the trees that show symptoms of the disease and it is likely that this process will continue throughout the summer as disease symptoms appear in further trees, culminating in felling the remaining stand of larch in the late autumn outside the bird nesting season.

“The disease is hard to see until the needles are out on the trees and it was not apparent until experts from the Forestry Commission, undertaking a survey, flew over the area recently and it became obvious that some trees on Hadborough were dead. If it is not controlled the disease could spread to other species damaging one of the special qualities of Exmoor, so our forestry team will be starting to fell the trees on Monday 24 May and we would ask people to keep out of the site to minimise the possibility of spreading the disease.”

The disease was first found in the UK in a garden centre in 2002 and has since been found mainly on viburnums and rhododendron. The Forestry Commission undertook a major survey of Britain’s woodlands where trees were mixed with Rhododendron ponticum and efforts were stepped up to remove rhododendron from woodlands.

During August 2009 at a site in east Cornwall laboratory testing confirmed Phytophthora ramorum present in rhododendron in the understory of mature Japanese larch. Subsequent testing at sites in north and west Devon and west Somerset confirmed the presence of Phytophthora ramorum in mature Japanese larch as well as species in its understory, including rhododendron, sweet chestnut, beech, birch, oak and Western hemlock. On some sites there is little or no rhododendron present showing a significant change in the way the disease is spreading.