FOREST experts have taken to the skies above North Yorkshire in a bid to tackle the spread of a deadly plant disease.

Forestry Commission experts have flown over North Yorkshire taking hundreds of aerial images of 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 helicopter flew over major forests such as Cropton and Dalby, near Pickering, as well as the Yorkshire Dales, Cleveland, Hambleton and Howardian Hills, and through the Vale of York.

The disease was first discovered on larch in the UK in 2009 in south west England and has since spread. No cases have been confirmed on the east of the Pennines, but forest chiefs say there is no room for complacency.

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 areas of concern can be pin-pointed and ground teams sent in to carry out a detailed inspection.”

Crispin Thorn, Forestry Commission area director for Yorkshire and the North East, said larch comprised 19 per cent of the productive area of woodland on Forestry Commission estates in North Yorkshire.

“Woodland owners and forestry contractors have a key role to play. The message is to be aware of the symptoms and act on suspicions.

Two films, produced to raise awareness of ramorum and its symptoms among landowners, forestry contractors and workers, forest visitors and the general public, can be viewed at forestry.gov.uk/phytophthorafilms.

Phytophthora ramorum is not harmful to humans or animals.