Explains the plant spirit practices used in sin eating and Celtic shamanism, and the nature of the soul and its maladies which can lead to illness, as well as the means of finding new health and balance through an understanding of our soul purpose, and the herbs, plants, and practices that can help with this. Ross Heaven is a psychologist, author, therapist, and plant spirit healer.
I'm probably not the ideal reviewer for this book, because it tends more towards Celtic Christian than Pagan Druid, which meant much of it didn't sit well with me.
For a person of the right background interested in working shamanically with plant spirits, this would make a good enough place to start. It's not a 'how to' book - there are things to explore, but its more for inspiraiton than exact detail.