Guide books such as this one are a good read, but can only be read after completing the series, due to mention of various spoilers such as the Pure Ones. This book is written by Otulissa, so therefore is in first person which gives the book its charm. The book also contains a marvelous poster of the tree, including passageways and secret chambers, such as The Band's Hollow and The Parliament.

'A Guide Book to the Great Tree' also includes a historical point of view, showing diagrams, such as Black Fire Mushrooms, which almost killed the tree a few centuries ago. There are also stories in the book, which are quite good also.

After reading the entire series (which I have already read twice (or thrice?)) this book is a great "topping" to the series. I hope you enjoy Kathryn Lasky's books. ( )