Richard Mabey's Flora Britannica became the ultimate flower book. Published four years ago, it succeeded in capturing a whole new readership for natural history guides. Although as big as a doorstep and costing £35 to boot, his magisterial account not only of Britain's wild plants but of the folklore surrounding them has so far sold more than 90,000 copies.
Now Mr Mabey is turning his face from flowers to feathers. Birds Britannica is on the way, aiming to be the last word on wild birds in Britain, documenting exhaustively the way we encounter them and the ways in which they impinge on our lives.
Did you know that pigeons have been seen travelling on the London Underground? Or that sparrows have set fire to a house? (They carried a smouldering cigarette on to a thatched roof). Can your parents remember that during the last war, people in Britain ate sparrow pudding, rook pie and moorhen stew?
This is the sort of modern folklore that Birds Britannica is setting out to capture, and it is doing so in the way that made its predecessor so distinctive: by relying on the knowledge, memories and stories of ordinary people as much as specialists.
Flora Britannica was distilled from the accumulated accounts of 10,000 contributors, each with their own tales of wild flowers or plants, responding to Richard Mabey's invitation to join in, which he made in letters, magazines and on radio. He now aims to repeat the exercise for birds.
Both projects were and are too big for one man, and for plant research Mr Mabey collaborated with the environmental charity Common Ground. For birds - with the project already running and scheduled for publication in 2002 - he is working with a full-time researcher, Jonathan Elphick, and has a co-author, Mark Cocker, himself an established writer on ornithology.
But there is no doubt that Mr Mabey is the principal attraction and that the new volume will be keenly awaited by the growing constituency, from professional critics to casual readers now recognising him as Britain's foremost writer on the countryside and the natural world.
More than 30 increasingly feted books produced since 1972 have made him the chief inheritor of an English literary tradition that goes back to Edward Thomas and Richard Jeffries, and indeed to the Hampshire parson Gilbert White and his groundbreaking account of the wildlife of his home village, The Natural History of Selborne, published in 1789. (Mr Mabey's 1986 biography of White, it should be said, won the Whitbread Biography of the Year award.)
Now 58, Mr Mabey is a reserved and intense man, but he carries his astounding store of knowledge about wildlife in all its forms with an attractive lightness of touch. His unexpected insights into the countryside can pull you up short. ("What's changed? There are hardly any children now," he says. "The countryside was full of children when I was a boy.")
Mr Mabey grew up - and still lives - in the Chilterns, not far from the majestic beechwoods. He closely followed the Environment minister Michael Meacher through Berkhamsted School and Oxford, although he was not an exact contemporary. "[Mr Meacher] was a prefect," he says, "when I was a fag."
He began as a jobbing writer with books on the class system and rock and roll, but found his true metier in 1972 with Food For Free, his account of all the good things to eat growing in the countryside and largely forgotten, such as samphire and fat hen. The book was an instant success, has never been out of print and has sold more than 200,000 copies, although it might not have done, Mr Mabey remembers with a grin, had he not insisted on his catchy title and resisted the publishers' attempts to name it "The Edible Plants of Hedgerows".
He agrees that Birds Britannica is not quite as mellifluous a title as that of its celebrated predecessor. "But I don't think something like 'Ornithologia Britannica' would really do," he says.
He is enthusiastic about the new project. "It's about how birds fit into our cultural, social and I suppose emotional lives. Everything from robins on Christmas cards to proverbs about one swallow not making a summer - but qualified, I hope, by all sorts of personal material, which shows that for most people, one swallow does make a summer, if it's a sign of spring," he says.
Mr Mabey and his collaborators would be only too happy to hear from anyone who has a British bird story, memory, anecdote or piece of information they want to contribute, which can be sent to Birds Britannica, c/o Random House, 20 Vauxhall Bridge Road, London SW1V 2SA.