The Nature of Oaks - The Rich Ecology of Our Most Essential Native Trees by Douglas W. Tallamy (2021 hardback 197 pp Timber Press $34.18)

I think Doug Tallamy, entomology professor at the University of Delaware, is one of the ecosystem gardening movement’s greatest ambassadors. His last book, Nature’s Best Hope, explained how we gardeners can save the planet if we all turn our outdoor spaces into ecological niches with native plants (70 per cent native is the rule if you want to ensure birds can raise a brood in your yard). Homegrown national park, he called it.

This book is about his love for one particular genus - Quercus, the oak. You have to read this book. Quite apart from anything else, it feels good in the hand. Well-bound, good paper, pleasing typeface, excellent photographic reproduction. And, it opens a window on what makes a tree great. Namely, good hosting - for more than 500 caterpillar species. “No other tree genus supports so much life.” What is a caterpillar? A walking leaf, in which the energy of the sun has been converted into protein for use by birds and other creatures up the food chain. And also, a future butterfly, which will delight us, or a moth, delightful and often puzzling. Don’t like caterpillars? Read page 79 on the harm of spraying.

Another greatness factor: oak leaf litter is the best, for supporting the decomposers that are a vital component of the underground web of life, for fighting invasives (because oak litter decays so slowly) and for improving water filtration (for the same reason).

Last year was a mast year for red oaks in our local forests and I gathered acorns that I grew in pots. This fall, no acorns fell - that’s the way with oaks, a year on and one or two years off. I planted my seedlings out in a special spot nearby, in honour of Doug Tallamy. To get a good tree with a healthy root system, you have to plant young, he says. “The smaller the better.”