The further adventures of Finn and friends had me right from the start! If you haven't read the first two books in the "Tree of Ages" series, I would suggest it. Although each book is very readable and enjoyable on it's own, the whole story is better.
Finn - who was once a tree - has few memories of her time before being a tree. They are important to remember, but could also be dangerous to her, the friends surrounding her, and even the world! It is a tumultuous, uncertain time - with magic reawakening and boundaries between the worlds of magic and mortals dissolving. As much as Finn may wish to deny her heritage, it is moving closer to her all the time. I don't believe in spoilers, so you'll just have to read it to see how it begins to shake out.
But if you love a good fantasy with characters that you can care about and a good series that leaves you wishing the next book was available as soon as you finish reading it, then check this out. All of Ms. Roethle's series will grip you and leave you wanting more!