Dartmoor National Park Authority

Phytophthora ramorum in Dartmoor National Park

An outbreak of Phytophthora was identified in the Plym Valley and Canonteign Woods last year and this summer there have been a number of outbreaks across the west country and into Wales.  Unfortunately, the infection has recently been confirmed in Japanese larch within Burrator Forest on land managed by South West Lakes Trust.

Phytophthora ramorum is a fungus-like infection that can kill trees and shrubs.  

It has been found on a range of tree species including sweet chestnut, beech, birch, oak, Douglas fir and Western hemlock. Whilst Phytophthora is found on non-native oak species in the UK, fortunately our native oaks appear to have a degree of resistance to the infection.  Infection is spread by spores which can be carried by wind, rain and air currents over several miles.  Spores can also be carried by people, animals and equipment.  

Burrator has roughly 400 hectares of woodland and it is estimated that about ten percent is Japanese larch.  The larch is found in single stands, in drifts and as an intimate mixture with other species.

The Forestry Commission have recently issued a Plant Health Notice that requires all of the larch within the forest to be felled by February 2011 and a programme of felling is planned. Initially the pure stands of larch will be felled, with a rolling programme to fell the rest of the larch throughout the year.

Dartmoor National Park Authority is working with South West Lakes Trust, South West Water, the Forestry Commission and contractors to manage the operations at Burrator. The National Park Authority is also working with the Forestry Commission to monitor woodlands on its own estate and on land that it manages for others.

There are significant archaeological remains throughout the Burrator estate and work will be carried out sensitively to avoid damaging these remains.  Areas of larch with no archaeological remains will be targeted in the first wave of felling. The more sensitive sites will be then tackled with advice from National Park Authority archaeologists.

The timber from infected trees can be used, but can only be processed by certified timber yards which have appropriate bio-security measures in place.  The trees can also be chipped for the bio fuel market as long as the chip is transported in covered trailers.

There is no risk to human or animal health and visitors do not have to be excluded from the forest, but the public are asked to minimise the spread of the disease by:

• keeping to marked paths, forest roads and hard footpaths;
• keeping dogs on short leads;
• not removing any plant material, such as cuttings, from the woodland;
• remove soil and mud from boots and shoes before leaving the woodland;
• keeping away from any felling operations and obeying any safety notices.

The Forestry Commission is the lead agency dealing with this outbreak and is currently undertaking a programme of aerial surveys throughout the South West, Wales and western Britain.  Phytophthora has been reported in other larch woodlands on Dartmoor and it is likely that more woodland will succumb to the infection.  Once an infection is identified a programme of clearance will be initiated in order to reduce the level of infected spores by removing Japanese larch, which is the principle host.

Useful links

http://www.forestry.gov.uk/pramorum (external link, opens new window)

News release issued July 2010

http://www.swlakestrust.org.uk/pramorum (external link, opens new window)

For information from Forestry Commisssion

Kirstie Smith, Communications Manager

Direct Dial - 01392 834249

Mobile - 07920 751106

For information from Dartmoor National Park Authority

Brian Beasley, Trees and Landscapes Officer

Jane Marchand, Archaeologist

Mike Nendick, Communications Officer

Tel: (01626) 832093

Page updated 20 July 2010