DOZENS of "wonderful" trees at a Herefordshire heritage site are to be felled.

Ash trees around Croft Castle, the National Trust-owned 17th-century manor house near Leominster, have become infected with a fungal disease called ash dieback.

It rots trees from the inside and makes parts or all of them at risk of falling onto footpaths used by visitors.

Contractors will get to work felling the worst-affected trees in Croft Castle's natural play area and picturesque Fishpool Valley in February next year.

Iain Carter, Herefordshire countryside manager for the National Trust, said: “The level of ash dieback in Fishpool Valley is severe, which is similar to many places in Herefordshire and throughout the country."

He said wet conditions in Fishpool Valley make trees there particularly susceptible to the disease.

"It’s very sad for our wonderful ash trees to be infected in this way, but we have to act quickly to guarantee public, staff and contractor safety,” he said.

The natural play area and Fishpool Valley will be closed to visitors during the felling, which is likely to continue throughout February.

The rest of Croft Castle's 1,500 acres of parkland – including the ancient tree walk, the Croft Ambrey walk, the Pokehouse Wood walk and the play area next to the tearoom – will remain open.

Ash dieback is an Asian disease which spread to the British countryside from imported trees carrying the infection six years ago.

Its spread is rapid, because the fungal spores can be carried by the wind for many miles. It is likely to affect up to 95 per cent of the country's ash trees.

In areas away from public footpaths and visitors, the trust is leaving ash trees standing to find out which specimens show tolerance to the disease, and then let them reproduce. Others will be felled.

Mr Carter said: “This is difficult and skilled work that we are likely to have to do more of at Croft Castle over the coming years.

"We need to manage the disease and mitigate for it, allowing other trees to flourish in place of the ash.”

The National Trust plans to re-establish native trees that would have populated Fishpool Valley before the ash became dominant, such as oak, chestnut, beech, lime and hornbeam.