The book traces the historical development of these rainforests in Britain, detailing how they have been shaped by natural processes and human activities over centuries.

These include ancient oak trees, rare lichens, mosses, and ferns, as well as unique animal species like the pine marten and the lesser horseshoe bat.

He discusses the contemporary challenges these ecosystems face, such as deforestation, agricultural expansion, and climate change, which threaten their survival.

Shrubsole explores how these ancient woodlands have influenced British culture, appearing in legends and stories such as the tales of King Arthur, which often depict enchanted forests as places of mystery and magic, as well as J. R. R. Tolkien and William Wordsworth.

"[2] The Financial Times called the book "remarkable", and wrote that "Shrubsole has completely changed the way many people look at the temperate woodlands that remain in parts of western Britain, fragments of which survive as havens of flora and fauna, as well as eerily evocative reminders of how much of the country used to look.