While I'm sure that many of the "facts" presented in this book are correct, the obvious errors make it incredibly difficult to trust anything Rowan says. On page 163 he begins to tell how each month relates to the tree. But Celtic astrology definately does not work in this way. Each month does not correspond to a specific letter of the ogham, nor to a tree. After all, you can't say that if you're born in September, you're a virgo. it doesn't work that way, and Rowan, as a bard or druid, should understand this. it leaves the reader questioning what other "facts" he has made up.
I was suprised and quite pleased with this book. It was scholarly and pragmatic. There is a lot to absorb here so one should take their time when reading it. It differs somewhat from the more typical druidic materials because as expected there is more emphasis on myth and music.