A case of the tree disease Chalara dieback of ash has been confirmed in a woodland in Devon. Devon is the 17th county in Great Britain where Chalara has been discovered in the wider environment, as oppose to recently planted trees. This brings the disease much closer to our own area of the south west, the next nearest being Carmarthenshire in South Wales, and emphasises the need to keep a careful watch for symptoms.
The disease appears to have been brought in with new planting, but has spread to some of the mature trees in the immediate local area. young trees are, however, no more than 17 years old, and Ben Jones, of the Forestry Commission, believes that the trees may have already had the disease when planted. Since the discovery just over a week ago, 1500 trees have been dug up and burned, in the continuing effort to control and slow down the spread of the disease. Volunteers from the Tanglewood Project helped with the clearance, and photographs of the work are courtesy of them. Felling and burning of mature trees is following on. Once the disease appears in mature trees in the wider countryside control will be almost impossible.
Maps and survey records continue to be updated on a weekly basis on the Forestry Commission web-site at http://www.forestry.gov.uk/chalara
Experts expect the mortality rate to be lower than Dutch elm disease, as ash is more genetically diverse than elm. Some strains of ash are expected to be disease resistant, with lesser consequences for woodland ecology, as some trees survive and adapt. However, that is small comfort for those who have invested in the planting and maintenance of young plantations.