One day last summer, Jake Fiennes was lost in a cloud of butterflies.

He was on a woodland path near Holkham Beach, on the north coast of Norfolk.

Every decade or so, ten million painted-lady butterflies, which are orange, black, and white, migrate to Britain from tropical Africa. The hot summer meant that it was a bumper year for native species, too, and the painted ladies mingled with red admirals, peacocks, and common blues, feeding on bushes set back a few yards from the path. “Just sat in a haze of flittering, fluttering butterflies,” Fiennes told me later. “I was in awe. These flowers were just exploding.”

Fiennes is the conservation manager of the Holkham Estate, one of Britain’s most important private landholdings. The estate covers about twenty-five thousand acres and includes a nature reserve, which is visited by almost a million people a year, and a farming business that grows potatoes, sugar beets, and barley, for beer. In 2018, Fiennes was hired by Holkham’s principal landowner, the eighth Earl of Leicester, to bolster wildlife across the estate, from its intensively farmed arable land to its wetland bird habitats. Fiennes describes what he does as “multifunctional farming” or “environmental farming.” He believes that farmers in the twenty-first century must cultivate as much as they can on their land—fungi for the soil, grasses for the pollinators, weeds for the insects, insects for the birds, pasture for the livestock—for the long-term goals of carbon capture and food production. “How do we feed the nine billion?” Fiennes said. “We feed them through functioning ecosystems.”

Fiennes told me to close my eyes. “What can you hear?” Fiennes asked. I was struck by the silence. After a moment, I could make out the small sound of a couple of birds, singing in the distance. “Generally, not a lot,” he said. During Fiennes’s lifetime, Britain has lost about forty-four million breeding birds. “This has become a natural, day-to-day thing that is not there,” Fiennes said. “This is what it is.”

The United Kingdom is a farmed country. Almost seventy-five per cent of the land is given over to agriculture—compared with some forty-five per cent in the United States. After the privations of the Second World War, the country joined a continent-wide push to banish hunger from Europe. Between 1935 and 1998, aided by chemicals, subsidies, heavy machinery, and crop science, British farmers more or less tripled their per-acre yields of wheat, oats, and barley. Milk production doubled. The amount of chicken meat offered for sale increased by a factor of twenty-five. Traditional farming methods, such as the Norfolk rotation, fell away.

Many seminatural habitats were drained or plowed under. An estimated ninety-seven per cent of hay meadows were lost. Between 1990 and 2010, the area of crops treated with pesticides in the U.K. increased by fifty per cent. The environmental damage caused by Britain’s intensive agriculture has only recently been properly understood. In 2013, twenty-five nature organizations published the first “State of Nature” report. “Even the most casual of observers may have noticed that all is not well,” Sir David Attenborough wrote in the foreword.

Researchers studied more than three thousand species and found that sixty per cent were in decline. Modern farming has been a nightmare for the familiar creatures—mole, rat, toad, and badger—of the British landscape. The 2019 “State of Nature” report concluded, “Farmland birds have declined more severely than birds in any other habitat.” More than half have disappeared in the past fifty years. We have one turtledove where we used to have ten. Sixty-eight per cent of starlings have gone, along with a quarter of our moths. In 2014, scientists found that lots in the city of Leicester contained a third more organic carbon—a standard measure of soil fertility—than the surrounding farmland.

turtle dove

Turtle Dove 

For ecological and political reasons, British farming has reached a turning point. When the country became part of the European Economic Community, the forerunner of the European Union, it joined the bloc’s Common Agricultural Policy, one of the world’s largest farm-subsidy programs. The C.A.P. consumes sixty-five billion dollars a year, about forty per cent of the E.U.’s budget; for decades, it has been criticized for its perverse incentives and environmental impact. In 2016, the C.A.P. was among the bureaucratic monstrosities of the E.U. that helped drive the vote for Brexit. Leaving the bloc has led to the first reform of agricultural policy in almost fifty years. “It is a reset moment,” Minette Batters, the leader of the National Farmers Union, told me. Beginning next year, British farming will transition to a new system of support, which will be linked to “public goods,” such as water quality and biodiversity. “We’re reinventing quite a lot of things at once,” Tony Juniper, the chair of Natural England, a public conservation body, said. “It does feel up for grabs.”

In a fluid moment, Fiennes’s ideas have attracted national attention. Juniper described Fiennes as “one of the motive forces behind this new way of looking at the land.” Geoff Sansome, the head of agriculture at Natural England, has worked with Fiennes for more than a decade. “Jake’s current canvas is Holkham, but he’s got his eyes set on a bigger canvas, quite honestly,” Sansome said. “He’s on a mission.”