EXPERTS have taken to the air and criss-crossed the region in an attempt to stop the spread of a killer tree disease.

The Forestry Commission team has flown sorties over North Yorkshire and County Durham as part of wideranging measures to save the region’s woodlands.

The flights by a helicopter involved experts taking hundreds of aerial images to spot tell-tale signs of infection caused by a fungus-like pathogen, Phytophthora ramorum, which kills larch trees.

The lethal disease was first discovered on larch in the UK in 2009 in the South-West and has since spread to many parts of western Britain, including Cumbria and Lancashire.

Although no sites have yet been confirmed east of the Pennines, forestry officials say there is no room for complacency as larch comprises 19 per cent of productive woodland in North Yorkshire and nearly eight per cent in County Durham.

Plant health operations officer Ben Jones 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.”

He added: “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 builtin GPS, areas of concern can be pinpointed and ground teams sent in to carry out a detailed inspection.”

The helicopter had been flying over the Yorkshire Dales, Cleveland, Hambleton and Howardian Hills, major forests such as Cropton and Dalby, near Pickering, Hamsterley Forest, County Durham, and through the Vale of York.

In another move to raise awareness of ramorum and its symptoms, 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, go to the Forestry Commission’s website at forestry.gov.uk/phy tophthorafilms