Sudden oak death spread to the UK in 2002
Trees and shrubs surrounding a medieval monument in Cardiff are to be removed and burned after a plant disease which can be deadly to trees was found.
The fungal infection known as sudden oak death was found at the Moundfield motte in Morganstown during works to conserve the 11th Century site.
A nearby football pitch is being shut temporarily while the burning takes place throughout the rest of 2009.
The site will be fenced off for up to five years until it is free of disease.
The infection, officially called Phytophthora ramorum, was detected on rhododendron bushes routinely tested as part of a conservation management plan for the motte, or fortified mound, in early November.
The council is working with the Department for Environment, Food and Rural Affairs (Defra) to destroy the affected vegetation.
The Moundfield site is waterlogged, which provides the fungal spores with an ideal environment to spread.
The motte is listed with Cadw and the conservation agency had to give permission for the work to be carried out.
Councillor Nigel Howells, Cardiff's executive member for sport, leisure and culture, said: "Outbreaks like this are beyond the council's control and we are acting quickly, under instruction from Defra, to contain and eliminate this problem.
"Unfortunately this area will have to remain fenced off for some while, with a football pitch also out of commission for several months.
"However, it is vitally important that we destroy all the infected plants to prevent this problem spreading and the measures we are taking are vital to ensure that this is done properly."
A Defra spokesman urged members of the public to observe access restrictions and to keep dogs on leads to prevent the infection from spreading further.
The disease is not harmful to people.