There is much to disagree with what George Monbiot writes and thinks, but he deserves some sympathy and support for his views on "rewilding" – allowing some agricultural land to revert to a non-managed or "wild" state.
We have some form on this. In 1994 we published "20-20 Vision: Targets For Britain's Future," and included a proposal to reintroduce beavers and wolves in remote parts of the UK, and even bears on some Scottish islands. There is evidence for the positive environmental effects, with beavers already aiding flood management in Britain, and grey wolves in Yellowstone National Park aiding tree growth by controlling deer populations, and creating habitats in which other wild creatures can flourish.
Monbiot called for us to give up meat and dairy products, so that agricultural land could be rewilded. Without going that far, Tim Worstall of this parish suggested that more efficient, industrialized farming could use less land and thus allow some farmland to grow wild again. He cited an example of the success of this:
New England. A century and a half back the area was a quiltwork of small farms. The forests we go to gawp at in autumn didn't exist, they'd been clear cut. What we do go to see these days is almost entirely new growth. Rewilding that has occurred as a result of mechanical farming and the railroads opening up the mid-West.
In summer we took this a stage further. A paper co-authored by Jamie Hollywood and myself looked at the prospects for cultured ("lab grown") meats, and concluded that this promised a new agricultural revolution. Cultured meats will probably soon be less costly than traditional meats from animals, and are rapidly improving in both taste and texture. This raises the possibility of using a tiny fraction of the land used in animal husbandry – less than 1 percent. This, in turn, would release land that could be rewilded. The UK's tree cover, estimated today at 13 percent, could be dramatically increased, creating huge new habitats for animals, insects and birds.
Some who oppose modern technology in agriculture because they prefer the traditional methods will not like this, but those who look to the advantageous outcomes it can produce will endorse it wholeheartedly.