1 April After a working life spent in a great museum, the time had come for me to escape into the open air. I spent years handling fossils of extinct animals; now, the inner naturalist needed to touch living animals and plants. My wife, Jackie, discovered the advertisement: a small piece of the Chiltern Hills up for sale. The proceeds from a television series proved exactly enough to purchase four acres of ancient beech-and-bluebell woodland, buried deeply inside a greater stretch of stately trees. The briefest of visits clinched the deal--exploring the wood simply felt like coming home. On 4 July 2011 "Grim''s Dyke Wood" became ours. I began to keep a diary to record wildlife, and the look and feel of the woodland as it passed through diverse moods and changing seasons. I sat on one particular stump to make observations, which I wrote down in a small, leather-bound notebook.

I was unconsciously compiling a biography of the wood--bio in the most exact sense, since animals and plants formed an important part of it. Before long, I saw that the story was as much about human history as it was about nature. For all its ancient lineage, the wood was shaped by human hand. I needed to explore the development of the English countryside, all the way from the Iron Age to the recent exploitation of woodland for beech furniture or tent pegs. I was moved by a compulsion to understand half-forgotten crafts and revive half-remembered words like "bodger," "spile" and "bavin." Plans were made to fell timber, to follow the journey from tree to furniture; to visit the canopy in a cherry-picker; to explore the archaeology of that ancient feature, Grim''s Dyke, that ran along one side of the plot. I wanted to see if the wood could yield food as well as inspiration. My scientific soul reawakened as I sought to comprehend the ways that plants and animals collaborate to generate a rich ecology.

I had to sample everything: mosses, lichens, grasses, insects and fungi. I investigated the natural history of beech, oak, ash, yew and all the other trees. I spent moonlit evenings trapping moths; daytime frolicking with nets to catch crane flies or lifting up rotten logs to understand decay. I poked and prodded and snuffled under brambles. I wanted to turn the appropriate bits of geology into tiles and glass. The wood became a route to understanding how the landscape is forever in a state of transition, for all that we think it unchanging. In short, the wood became a project. Grim''s Dyke Wood is just a segment in the middle of more extensive ancient woodland, Lambridge Wood, lying in the southern part of the county of Oxfordshire.

Splitting Lambridge into separate plots generated a profit for the previous owner, but also allowed people of modest means to own and care for their own small piece of living history. Our fellow "woodies"--as Jackie terms them--proved to include a well-known harpsichordist, a retired professor of business systems, a founder member of Genesis (the band, not the book), a virologist turned plant illustrator, ex-actors turned psychologists, and a woman of mystery. Our own patch is one of the smaller ones. All of the "woodies" have their own reasons for wanting to be among the trees--some desire simply to dream, some would rather like to turn a profit, others to explore sustainable resources. I believe I am the only naturalist. All the owners are there to prevent the wood from being felled or turned into housing. For the long history of Lambridge Wood tells us that our trees are less worked today than at any time in the past. This sad redundancy is no less part of its tale, as our wood is inevitably connected to the wider world of commerce and markets.

The histories of my home town, Henley-on-Thames, a mile away, and the famous river on which it sits are bound into the narrative of the surrounding countryside. Ancient manors controlled the fate of woodlands for centuries. I have to imagine what the wood would have seen or heard as great events passed it by; who might have lurked under the trees, what poachers and vagabonds, poets or highwaymen. Once the project was under way a curious thing happened. I wanted to make a collection. This may not sound particularly remarkable, but for somebody who had worked for decades with rank after rank of curated collections it was rejuvenation. Life among the stacks in the Natural History Museum in London had stifled my acquisitiveness, but now something was rekindled. I wanted to collect objects from the wood, not in the systematic way of a scientist, but with something of the random joy of a young boy.

Perhaps I wanted to become that boy once again. Eighteenth-century gentlemen were wont to have cabinets of curiosities in which they displayed items that might have conversational or antiquarian interest. I wanted to have my own cabinet of curiosity. I would add items when my curiosity was piqued month by month: maybe a stone, a feather or a dried plant--nothing for the eighteenth-century gent. I believe that curiosity is a most important human instinct. Curiosity is the enemy of certainty, and certainty--particularly conviction that other people are different, or sinful, or irreligious--lies behind much of the conflict and genocide that disfigure human history. If I could issue one injunction to humankind it would be: "Be curious!" My collection will be a way of encapsulating the whole Grim''s Dyke Wood project: my New Curiosity Shop. And I already know that the last item to be curated will be the leather-bound notebook.

The collection requires a cabinet to house it. Jackie and I plan to fell one of our cherry trees and convert it into a wonderful receptacle for the wood''s serendipitous treasures. We must discuss the work with Philip Koomen, a noted Chiltern furniture-maker devoted to using local materials. Philip''s workshop, Wheelers Barn, is in the remotest part of the Chiltern Hills, only about five miles from Grim''s Dyke Wood as the crow flies, but about fifteen as the ancient roads wind hither and thither. His studio is imbued with calm. Polished sections through trees hanging on the walls show the qualities of each variety: colour, texture, grain and age all combine to distinguish not just different tree species, but individual personalities. No two trees are identical. Some have burrs that section into turbulent swirls.

Pale ash contrasts with rich walnut, and cherry with its warm tones is satisfactorily different from oak. This is a man who cares deeply about materials and believes in the genius loci--an integration of human and natural history that lends authenticity to a hand-made item. Philip''s handiwork from our own cherry tree will be a physical embodiment of our wood, but by housing the idiosyncratic collection picked up as the project develops, it will also contain the wood, as curated by this writer. It will be a cabinet of memories as much as objects. We haggle a little about design, but I know I shall rely on his judgement. I will have to be patient when I gather up the small things in the wood that take my fancy. It will be some time before the collection can live in its dedicated home. This book could be thought of as another kind of collection.

Extracts from my diary describe the wood through the seasons. I follow H. E. Bates''s wonderful book Through the Woods (1936) in beginning in the exuberant month of April rather than with the calendar year, and frigid January. But then, H. E. Bates himself inherited the same plan from the writer and illustrator Clare Leighton, whose intimate portrait of her own garden through the cycles of the seasons, Four Hedges,1 he much admired. My friends and colleagues come to sample and identify almost every jot and tittle of natural history that they can find.

Natural history leads on to science, and the stories of grand estates, woodland skills and trades, and life along the River Thames. Human folly and natural catastrophes link the wood to a wider world beyond the trees. This complex collection explains why the wood is as it is today; its rich diversity of life is a concatenation of particular circumstances. I am trying to reason how the natural world came to be so varied, and my understanding is refracted through the lens of my own small patch. I am trying to see the wood for the trees. Bluebells Some trees stand close together, like a pair of friends huddling in mutual support. Others are almost solitary, rearing away from their fellows in the midst of a clearing. The poet Edward Thomas described "the uncounted perpendicular straight stems of beech, and yet not all quite perpendicular or quite straight.

"2 Each tree trunk has individuality, for all the harmony of their numbers together. One leans a little towards a weaker neighbour; another carries a scar where a branch fell long ago; this one has an extraordinarily slender elegance as it reaches for its place under the sky; that one has a stocky base, as chunky as an elephant''s leg, and doubtless at least as strong. No two trees are really alike, yet their collaboration on the scale of the wider wood creates a sense of architectural design. The relatively pale and smooth beech bark helps to unite the structure, for in the early spring''s soft sunshine the tree trunks shine almost silver. The natural cathedral of the wood is supported by brilliant, vertical superstructure, one that shifts subtly with the moods of the sun. It is too early in the month for many fresh beech leaves to have unfurled from their tight buds. The wood is still flooded with light. Some of the sunlight falls on the crisp, dark tan to gold-coloured leaves fallen from last year''s canopy that lie in scruffy patches on the ground; stubbornly dry, they have yet to rot away.

The sunshine brings the first direct heat of the year, enough to warm our cheeks with hi.