If you are a British gardner, and wish to buy only one book on woodland gardening, you will want to choose Karan Junker's modern English classic
Gardening with Woodlands Plants; Larry's book is an American equivalent, but if you are a collector of gardening books, or simply want another slant, you will want to buy this one, too, even though it mentions only 200 plants (each one illustrated), compared to Karan Junker's 2,000.
It is written breezily, is easy and enjoyable to read, whilst displaying the specialised, in-depth, hands-on, horticultural expertise which gives the reader confidence, and I found here one or two ingenious tips on dealing with the woodland environment that I have never seen elsewhere or thought of myself in 40 years of daily woodland gardening. Every plant gets two full pages, and the selection is excellent. The author's experience is in a part of the USA which routinely suffers far worse winters than we normally do, and if you followed the advice herein, you could not fail.