Richard Mabey on the beauty of the beech

Tall, majestic, hardy – the British beechis the king of the forest, argues our leading naturalist, Richard Mabey. Rob Sharp takes a walk in the woods with the man himself

The most striking piece of trivia about the Queen beech, a gnarled, knotted old tree in an ancient Hertfordshire woodland, is that it was once a character in a Harry Potter film. The landmark at Frithsden Beeches, just outside London, took a turn as the sometimes violent Whomping Willow in The Prisoner of Azkaban. You can see why the film-makers were struck by it: it looks good for a 350-year-old. Regal limbs creep out from its centre; it has the grandeur of a seen-it-all veteran that has lived since before the Great Fire of London, and taken in plenty more besides.

If one could pick the ideal companion with which to encounter this majestic and spooky scene, it would surely be Richard Mabey. Softly-spoken, intense and erudite, he is one of the "wild bunch" of lyrical writers currently riding a wave of interest in man's relationship with the landscape. His drinking buddies include Crow Country scribe Mark Cocker and Cambridge University don Robert Macfarlane, author of the recent hit The Wild Places. Among his peers, Mabey's name is uttered with a hushed reverence. In the world of the green-fingered literary gurus, he is king.

The beech is Mabey's favourite tree. He spent much of his childhood playing in the beech woods of the Chilterns, and once owned a beech wood himself. He admires the tree's amazing ability to respond to catastrophe. Today, beech woods criss-cross southern England, from Burnham Beeches to the New Forest and the Chilterns.

Unlike the high-profile oak, Mabey calls beeches the "workhorses of the forest". They provide firewood and furniture, and epitomise nature's capacity to respond to change. They also play host to many organisms, from hawks in their branches to toadstools on the ground. The Wild Wood in The Wind in the Willows is, inevitably, a beech wood.

All this is chronicled in Mabey's eagerly-awaited new book, Beechcombings, the Narratives of Trees. Released next month, it describes the beech's characteristics, habitat and mythology, and explores what we, as humans, can learn from the world of trees.

Most people, of course, take beeches for granted. They are viewed as biological barriers to motorway construction. But throughout history, natural selection has provided them with a long-standing ability to adapt to day-to-day environments (an adaptability that makes humans look like sallow, spluttering wrecks in comparison).

Sadly, they were also one of the main casualties of the famous 1987 hurricane, the 20th anniversary of which comes round on 16 October. Mabey believes the so-called "great storm" was a significant landmark in the tree's ancient cultural history.

Like much of the work of the "wild bunch", Beechcombings is touchingly personal. Mabey grew up near Frithsden Beeches, and still regularly visits. When we meet to tour the woods, he escorts me with a sort of second sight, rattling off the history and mythology of the trees with zeal. Bathed in a cathedral of diffused light from the canopy, he is as fluent discussing their morphology as their significance to his life.

Frithsden Beeches has an ancient and important history. In the 11th century, William the Conqueror based himself nearby after the Conquest, and would have stared across them while contemplating a new kingdom. Over the years, the area has provided vast amounts of space for hunting, as well as supplying local firewood.

"It was a large area of wooded common land, and therefore like all commons it was sought after by landowners for other purposes," Mabey says as he stumbles through its undergrowth and trunks. "There were repeated attacks on it over the years and these were rebuffed by locals on a number of occasions."

This trend came to a head in the 1860s, when the woods were seized by landed gent Lord Brownlow. His agents, Mabey says, illegally enclosed the common behind four miles of fencing. They were thwarted by Augustus Smith, a local landowner with a conscience who he describes as a "radical precursor of [campaigning environmentalist] Jonathon Porritt."

"Smith was distressed because Brownlow had done it in underhand way," says Maybey. "He should have gone through the proper channels in Parliament." Smith hired a 120-strong rent-a-mob to tear down the fencing in March 1866, finishing the job in a single night.

The beech has survived because it is a hardy species. It casts a long shadow and, as a result, many other species, such as birch and oak, do not get the sunlight they need to grow high around it. Beech saplings are also steely growers, enabling them to thrive on poor soil, including chalk. They blanket parts of the Chilterns, the South Downs and the Cotswolds.

When a beech tree, like all other trees, is "wounded", it does not heal the lesion as an animal would. Instead it seals off the graze or cut, isolating it from the rest of its "body" via a large, warty canker. The Queen beech has these in spades. You can also see evidence of how some trees cope with high winds. In some cases, if one is uprooted, it can produce new shoots, phoenix-like, from a seemingly ruined root system. Tree populations can also cope with strong winds because many of the more elderly ones are hollow, their insides long rotted away; this dramatically reduces their centre of gravity.

While many beeches in Fristhden survived the 1987 storm (often the hollow ones), plenty were felled. In the areas of Britain that experienced the worst of the winds –the South-east – the beech was the hardest hit tree of all; by weight, 40 per cent of all fallen timber was beech.

Twenty years on, many of the fallen trunks have been cleared up, the latest instalment in an ongoing debate over whether man should interfere in such matters. In post-storm 1987, the National Trust, which looks after the wood, did not believe that fallen trees met with the public's perception of what "a wood should look like", and so got rid of them. Over the ensuing years it transpired that much of the NT's man-made regeneration and planting was not successful. In areas where no one intervened the wood has begun to flourish. It has since become National Trust policy to intervene much less, Mabey explains, except where public safety is at risk.

"The hurricane made one aware that natural systems aren't stable," he says. "We in this country have always had an idea of nature as something peaceful, contrasting with the energy of a city. The storm demonstrated this was not the case. It showed living systems are fantastically dynamic; and need to be to survive."

The author summarises the importance of such "dead trees" to the environment. "Trees are terribly important for fungi and insects," he continues. "In a totally unmanned wood, 50 per cent is dead wood. So it is of equal importance, ecologically, to so-called live wood. It also protects regenerating seedlings from animals, and then there's the philosophical question: the natural way is to leave it the way it is. The onus is on the person who wants to remove the wood to explain why they are doing it."

Mabey once owned Hardings Wood, located close to Fristhden in the village of Wigginton. He bought it in 1981. But after publishing the book many critics believe he will be best remembered for, Flora Britannica, in 1996, he sunk into a depression, moved east, and flogged it to a trust run by local residents. The ensuing "sense of dislocation" he felt formed the basis of his 2005 book Nature Cure, about how he used nature to revitalise his mental health.

Several miles away from Frithsden, on a brisk autumnal evening, we find Hardings growing on strong, just as when Mabey left it. Felled wood is packed neatly by the path at the wood's entrance. Mabey says of selling it: "My friends were surprised. I didn't feel like I'd put it all behind me; I didn't feel like I was severed from them at all. It was a mere inconvenience, not a barrier at all. There was no emotional barrier."

Later, along the track leading out of the centre of the wood, Mabey discovers that a single cherry, one of "his favourites" has died. It is an awkward moment. He leans over a gate, staring at a panoramic bowl of landscape, the distant beeches of Frithsden visible where land meets the sky. He smiles, acknowledging an internal emotion that I'm not privy to, before, as the old joke goes, making like a tree.