Flights help pinpoint tree disease

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AN “eye in the sky” is targeting damaging disease in larch trees in the area around Clitheroe.

A Forestry Commission team has flown sorties over Lancashire as part of wide-ranging measures to tackle the spread of a deadly disease of larch trees.

The helicopter flights involved experts taking thousands of aerial images of local woodland to spot tell-tale signs of infection caused by a fungus-like pathogen, Phytophthora ramorum
(P. ramorum), which kills larch trees very quickly.

The lethal disease was first discovered in the UK in 2009 in South West England, and has since spread to many parts of western Britain, including Lancashire, where nine sites have been identified, mostly around the Clitheroe and Burnley areas.

Flights have not so far found any significant signs of further infection, but analysis continues and vigilance is vital.

Ben Jones, Forestry Commission England’s plant health operations manager, said: “Containment and early felling is important because infected larch trees produce huge numbers of the spores that spread the disease.

“These can be spread some distance from tall trees by the wind and in mists, risking rapid spread of the infection to large numbers of other trees.

“The helicopter covers large areas of ground quickly, giving us a good view of the forest canopy.

“That means we can look for disease symptoms like dead tops and branch and shoot dieback with a distinctive ginger colour, as well as any other abnormalities.

“Using cameras with built-in GPS means that areas of concern can be pin-pointed and ground teams sent in to carry out a detailed inspection. We started flights in 2010 and they have proved incredibly useful.”

Larch trees comprise about 1.2% of all woodland in Lancashire, and the North West is deemed a high-risk zone for
P. ramorum infection because of its moist climate.

In another move to raise awareness, two films have been produced by a partnership of agencies aimed at landowners, forestry contractors and workers, forest visitors and the general public.

To view them online, go to the Forestry Commission website at

Further information is available at