Anyone interested in Paganism, Witchcraft, or Wicca really should own this book. I cannot recommend it highly enough. It is fluff-free and academically, though not poorly, written.
This, along withThe Witches' Goddess: The Feminine Principle of Divinity, provides and excellent introduction to Wiccan concepts of divinity. Both books are well researched and as complete as can be expected given the enormity of the subject.
If your studying herbs or medicinal plants this book should NOT be on your list of books to own. IT IS WORTHLESS! It is a Pagan Religion Book. Plain and simple! In my opinion it is for the study of WITCHCRAFT and the like.