As a boy, the great 19th-century naturalist writer Richard Jefferies would walk up Liddington Hill above Swindon: "Moving up the sweet, short turf, at every step my heart seemed to obtain a wider horizon of feeling; with every inhalation of rich pure air, a deeper desire." There he would lie on the grass thinking of all those humans and animals who might have been buried beneath it and listen to the skylarks, their song "like a waterfall in the sky".
Something of the same tone of mordant elegy sustains Tim Dee's contemplation of the decay of nature, which also has a chorus of larks as he ranges from his home fen field in Cambridgeshire to the edgelands of Namibia and Montana. The last and darkest of the four fields he chooses, near Chernobyl, has fewer larks, but with a Swedish biologist, he muses on the genetic mutations caused to swallows by radiation; some 20 per cent have been affected, although it seems extraordinary and moving that they should return at all to those dark woods.
Dee, along with Richard Mabey, is one of our finest naturalist writers; his first book The Running Sky was a superb meditation on bird-watching, as was, in a different way, the anthology he edited with Simon Armitage of The Poetry of Birds. He is incapable of writing a dull sentence about an animal: he sees the "jewelled toolkit of a kingfisher" flash past or notes how "hares moved off stiff-backed with their odd, humping limp. Their long hind legs afflict them with a kind of virile disability, as if to walk were always more taxing than to run." A rook is a "photographic negative of a seagull".
As over a year he lets the grass grow under his feet in the Fens, he reminds us how little we appreciate Jefferies's "sweet, short turf". The three great food crops of the world are grasses: rice, corn and wheat. Yet grass is a newcomer by botanical standards; it only came to dominate the northern hemisphere in the last 12,000 years, around the time homo sapiens arrived on the plains of North America.
His threnody on how those grasslands were enclosed, robbing the plains Indians of their heritage, segues naturally into a discussion of enclosure elsewhere. For a field is by definition nature contained and stolen, as John Clare – a touchstone for the project – is just one of many literary wanderers over the greensward to complain.
While the battle of Little Bighorn may be a familiar story, his account of the slow death of a Namibian farmstead near the desert is not, and is the finest section in the book. Dee's vision is at its most scalpel-like as he examines road-kill swallows or the bloated bodies of wildebeest piled up in rivers where they have failed to make the crossing.
When the reader is lulled by a rare moment of anthropomorphising – a friendly honeyguide bird, who leads the author to a bees' nest so they can share the feast - any cosiness is soon subverted. That same honeyguide leaves its eggs cuckoo-style in the nests of other birds, and when one hatches, it savagely murders all the other blind fledgings.
As with much of the "new nature writing", Four Fields is an austere read, packaged to look like a Joy Division album; there is only one joke, on page 203, and by then we've reached Chernobyl. Earlier exponents of the genre, like Jefferies or the engaging Robert Gibbings, could temper their vision of nature red in tooth and claw with more bucolic moments. Good as this is – and it is very good indeed - one can't help wishing that Tim Dee might occasionally turn his sublime gifts to sunnier pastures: if not a summer in Tuscany, at least a picnic on the Downs.
Hugh Thomson's 'The Green Road into the Trees: An Exploration of England' is published by Windmill