Great Green Wall

There is a delightful moment at the end of this book when Frank Ashwood is out looking for soil-dwelling invertebrates in his adopted New Zealand home. Suddenly he proclaims: ‘I notice something and my heart skips a beat. A velvet worm.’ He goes on to tell us that the discovery of two of these rare organisms in one day is ‘a thing of dreams’. Far from scoffing at his excitement, the reader has long come to share his enthusiasm for the extraordinariness of velvet worms. They are, after all, lozenges of blue and orange stripes rolled in tiny sequins. That we have also come to see the full beauty, abundance and sheer weirdness of the whole subsoil realm is a measure of Ashwood’s wider achievement.

A decade ago, I planted 12 acres of trees in a field that had proved unsuitable for productive grazing. The trees themselves are doing well but the most remarkable change has been the increase in birds, invertebrates and flora. Each year brings new species, new levels of abundance. It has been very satisfying and strangely quick. We’re encouraged to think that the planet’s natural processes work if not always at a geological pace, at least not in the instant reward timeframe that characterises our own brief lives. In Nature’s Echo, the leading ecologist Thomas Crowther takes this capacity for nature’s rapid recovery as one reason why we should temper pessimism about environmental catastrophe.