‘Does rewilding sort climate change? Yes!’: UK expert says nature can save planet and not harm farming

Biodiversity campaigner Isabella Tree says wild areas work ‘hand in glove’ with food production as her Sussex estate boasts return of endangered species

The Knepp estate in West Sussex is home to the first white stork born in the wild in Britain for over 600 years. It’s a place where endangered bats, turtle doves and nightingales are thriving, where “officially extinct” large tortoiseshell butterflies are breeding and where tens of thousands of people visit each year to experience “a story of hope” about the resilience of nature in the face of the global climate emergency.

There have been many exciting changes at Knepp since 2018, when Isabella Tree wrote Wilding, her award-winning book about rewilding an unprofitable 3,500-acre arable and dairy farm. Now she has written a captivating illustrated book, Wilding: How to Bring Wildlife Back – An Illustrated Guide, updating her readers about extraordinary developments at Knepp and offering practical advice about rewilding their own spaces, however small.

“We’re living in a world of eco-anxiety and most of us, I guess, stick our heads in the sand because these problems are so enormous,” says Tree. “How is one individual going to make a difference to climate meltdown and biodiversity? ‘It’s impossible,’ you think. Then you come to Knepp and you see what nature has done, how it’s rebounded in 20 or so years. It really is such a story of hope that I think people find it quite galvanising. It restores your energy and your belief that you can do something.”

The book, out on 7 March and is aimed at older children (aged 9+) and adults, explains how and why Tree and her husband, Charlie Burrell, sold off their dairy cows and farm machinery in 2000. They stopped ploughing and spraying fertilisers and pesticides, pulled up their barbed wire fences, smashed their Victorian land drains, quit clearing their ditches – and “simply let things go”. “We wanted to work with nature for a change, rather than fighting against it all the time,” writes Tree.

Exquisite illustrations by the printmaker and fine artist Angela Harding reveal how, step-by-step, wilderness and wildlife then returned to Knepp. “Nature bounces back, if you let it, wherever it can.”

Some of the rarest creatures in Britain have now made Knepp their home, including kingfishers, hazel dormice, scarce chaser dragonflies and purple emperor butterflies. The river has returned to its natural course and the soil is now storing as much carbon per hectare as a 25-year-old plantation of trees does, according to recent tests.

“That’s really exciting, because rewilding has been seen as fantastic for wildlife and recovering biodiversity, but people say it doesn’t answer the problem of climate change. We can say now, categorically, it does. That, actually, you can restore your soils by allowing an area to rewild – and just the soils alone will be the same as a carbon storage in a plantation.”

This comparison is important, Tree says, because putting trees in the ground with a spade is not good for biodiversity. “What you’re creating as a single generational plantation with standing trees is a closed canopy woodland, which is very species poor.” By contrast, Knepp has wetland, scrubland, mature trees and deadwood, as well as mycorrhizal fungi and root systems under the ground. “All of that is way more significant for storing carbon than just planting trees.”

Yet, in 2000, Knepp was merely an “unpromising piece of land underneath the Gatwick stacking system”. “If it can happen here, it can happen anywhere.”

The release two years ago of a pair of breeding beavers was particularly important: last year, they had two kits, the first to be born in the wild in Sussex for centuries. “Seeing what the beavers have done during all these storms and floods is astonishing – they’re holding back probably four or five acres of standing water and helping to prevent flooding downstream.”

During the 2022 heatwave, the beavers’ dams created something similar to a “little emerald oasis in the middle of an African savannah”, which is now “heaving with life”.

Tree says: “It’s absurd we still have to have beavers under licence in enclosed pens in England, when they’re living free in Scotland and on the continent. Everyone knows how powerful they are for cleaning polluted water and restoring biodiversity.” She and Burrell have been campaigning to “get beavers back in England” for 15 years: “We’re so risk averse in the UK, while the planet is in meltdown. We’ve got to get braver and start reintroducing the keystone species that are crucial to restoring nature.”

Wild-living beavers were recently given protected status in England, but farmers are concerned that reintroducing the native species – which was hunted to extinction in the 16th century –will threaten their crops or livestock, for example by redirecting rivers and flooding agricultural land. Similarly, critics of rewilding argue that the government’s decision to offer farmers incentives to rewild their land, in order to restore 741,000 acres of wildlife habitats in England by 2042, is putting food security at risk, when the UK is already heavily reliant on global food supply chains.

“People say we can’t rewild everywhere – how are we going to produce food? That’s the big pushback we’re getting against nature, certainly from the National Farmers’ Union,” says Tree.

While she accepts that not everywhere can be rewilded – “we will always need land for food production” – she thinks that it can protect crops and provide farmers with a “life-support system” they desperately need.

“We cannot carry on ploughing and using chemicals and artificial fertiliser. We know the pollution that causes, we know we’re losing our soils. So, for the long-term security of food production itself, we’ve got to shift to regenerative agriculture. But also we need to have rewilded areas around our food production to provide the dung beetles, the pollinating insects, the pest control, the clean water, the water storage and the buffers against extreme weather events.”

Surrounding agricultural land with wild land is the only sustainable way forward. “Rewilding works hand in glove with food production. We can have both,” she says. “We’ve got the space for both.”

Cover photo: Isabella Tree, author of Wilding and architect behind the wilding project at her home on the Knepp estate. 19 July 2021 Picture by Jack Hill/The Times and Sunday Times. Photograph: Jack Hill/The Times