Before the discovery of a number of mature trees infected by Chalara dieback of ash in Carmarthenshire, the disease had been confirmed only in newly planted sites in Wales where the trees could be traced to nurseries known to hold infected stock.
The disease, caused by the fungus Chalara fraxinea, has already been found in the wider environment in the south-east of England and on the eastern side of Scotland since it was first recorded in Britain in early
It had been discovered in 19 recently planted sites in Wales, but this latest development marks the first discovery of Chalara in the wider environment on the western side of Great Britain.
The infected area, in Ferryside, south of Carmarthen, was discovered by Natural Resources Wales (NRW) staff during a routine inspection earlier this month. It is adjacent to a site which was planted with young ash trees between December 2006 and March 2007, some of which also have the disease. Samples were sent for scientific analysis, which confirmed the trees had become infected with Chalara.
John Browne of NRW said: "Following the discovery of Chalara dieback in the wider environment in England last autumn, we have known that it would be only a matter of
time before it was discovered in the wider environment here as well.
"We have carried out a 1.5km survey of the area to ascertain the extent of the infection, and we are liaising with the landowners on the steps they can consider to reduce the rate of spread of the disease, in line with the Welsh Government's Wales Chalara Management Plan."
NRW is working with the Welsh Government on a UK-wide response to tackle the disease in conjunction with the Forestry Commission, Defra, the Food & Environment Research Agency (FERA) and the devolved administrations in Scotland and Northern Ireland.
A ban on movements of ash plants and seeds into and within Great Britain has been in place since October 2012 to help slow the spread and minimise the impact of Chalara.
Contact www.forestry.gov.uk/treealert, or call the Chalara helpline on 08459 335577.