London's cemeteries are too well kept for wildlife to flourish, according to experts attending the first conference dedicated to preserving them.

Conservationists fear these mini-ecosystems are at risk from 'over intensive' administration which results in manicured lawns and immaculate hedgerows, and they want to see cemetery managers let the foliage run wild.

Peter Sibley, ecology officer with Southwark council, which is running today's seminars with English Nature at the London Wildlife Trust Centre in Peckham, said he was concerned about the use of herbicides and pesticides.

'We regard cemeteries and churchyards as some of the most valuable areas for nature conservation in London. They are the air conditioning units of the city if you like, but I wouldn't want people to think that we are putting up a fence around them.'

He said three species of British woodpecker had been sighted at Nunhead cemetery in Southwark and at least one is breeding successfully.

A resident pair of tawny owls also nest in the graveyard, as they have for generations, sustained by the abundance of small mammals that make their homes among the graves.

Julie Rugg, from the University of York, who recently conducted a nationwide survey of cemetery use, believes the needs of humans and animals can be accommodated.

'Cemeteries have areas which are no longer visited and this is where they could be allowed to grow untended and support the wildlife,' she said.

'But in areas where people have only been buried recently, their relatives want to see that the place is being cared for and I can fully understand that.'

Today's seminars, which will concentrate on cemeteries and churchyards in the capital, are intended to find a common policy which would suit both the flora and fauna in the plots as well as people who visit and tend to the graves.

The conference will focus on the 'Magnificent Seven' - the cemeteries created between 1830 and 1850 which formed a ring around what were then the outer limits of the city.

They are: Highgate, Abney Park (Hackney), Tower Hamlets, Nunhead (Southwark), West Norwood, Brompton (Kensington) and Kensal Green.

According to Mr Sibley London's burial grounds are now almost full and increasingly people are having to look further afield to bury their dead. 'Many people are having to be buried either just inside the M25, or even outside it now.'

(Photograph omitted)