“Trees fit in well in many places where it’s not suitable to do tillage agriculture. You can use hillsides, where, any time regular monoculture agriculture occurs, it causes a lot of erosion and soil loss. Having trees in these places slows erosion, starts to rebuild soil, and sequesters more carbon,” he says. It also adds diversity to the food system, which helps build resilience to food shocks. While chestnuts may not be commonly eaten today, for example, they are a great source of carbohydrates that could, in theory, replace grain or corn in our diets. “It’s basically growing grain on a tree,” adds Neiger.

The practice of incorporating trees into agriculture is known as agroforestry, and it has been practised for thousands of years in a number of variations. Some involve planting trees on existing farmland, while other methods use an existing forest as a living laboratory for growing shade-loving species.

For instance, the traditional hedgerows that enclose many English fields are an unremarkable sight for many people, yet they provide many ecological benefits including opportunities for foraging and a habitat for wildlife like hedgehogs. Less familiar are methods such as alley cropping, where trees are planted in wide rows with crops grown in between them. The approach practiced at Big River Chestnuts farm is known as forest farming, a technique which involves the intentional cultivation of plants beneath the forest canopy (as opposed to foraging for wild species in an existing forest).

These methods can avoid many of the pitfalls of our current food system, which has caused a precipitous decline in biodiversity and currently contributes around a third of global emissions. But forest farming also provides an incentive to protect existing forests themselves, by giving them an economic reason to remain standing, rather than being logged or cleared. Forest farms are usually associated with high-value species that thrive in a shaded environment, including foodstuffs like shiitake mushrooms, but also herbal and medicinal plants.