Beside a lane I walk down every morning these days, there are two enormous old oaks, their trunks distorted by huge burls. They must be at least four hundred years old, probably more; they show up, fully grown, on a map printed two hundred years ago. I’ve always admired these trees, but the fact is that all I could say about them is what I can see of them, clinging to the hillside in stately silence, throwing shade over browsing cattle, harbouring blackbirds. That was until I read Finding the Mother Tree.

Suzanne Simard is an ecologist whose speciality is the underground life of trees and whose findings have revolutionised the way we think about them. Growing up poor in the backwoods of western Canada but blessed with an extraordinary degree of natural curiosity, she fell into studying this hidden world almost