Ancient oak trees in Hampstead and Highgate up to 2,000 years old are at risk of being chopped down to make way for basement works, a leading member of the Highgate Society has said.

Society vice-president Michael Hammerson, who sits on the society’s environment committee, wants to protect more than 800 trees in the area after many others have been chopped down as part of building works or because they are rotten.

He said felling the trees, all more than 250 years old, should always be a last resort.

“These trees are so historically and ecologically important,” said Mr Hammerson, of Highgate Village.

“Trees can be treated [for rot] and reduced so they can remain stable for centuries.

“What the Highgate Society wants to do is to raise awareness of the importance of them and, in terms of looking after them, getting the best advice possible if there’s an issue that is really essential.”

Mr Hammerson said several trees in back gardens have been felled as part of basement works.

The City of London Corporation, which runs Hampstead Heath and Highgate Wood, has also voiced concern about several planning applications which sought to fell trees in Hampstead and Highgate.

Its tree specialists are currently working with Camden, Haringey and Barnet councils to highlight the issues around the management of ancient trees.

Jonathan Meares, Highgate Wood conservation manager at the City of London Corporation, said: “As the City of London Corporation invests a considerable amount of time and effort managing the 800 veteran trees on Hampstead Heath and the ancient woodland of Highgate Wood, we are keen to provide our support and expertise to local authority colleagues to ensure that these trees receive the protection that they deserve and are recognised for their great historical and conservation importance.”

Some of the trees in Highgate Wood are between 1,000 and 2,000 years old and are survivors from the lost 1,000-acre Bishop of London’s Hunting Park, which dates back to the 12th century.

Mr Hammerson advises residents to contact an arboriculturist or the Highgate Society for advice about managing ancient trees in their gardens.

Planning permission must be obtained from the council before trees in the Highgate or Hampstead conservation areas can be chopped down.