This is very ambitious work and I appreciate writing about nature in that scope. Powers really brought trees closer to people and did not shy away from sharing scientific knowledge. 
I was very excited to read this book knowing what was it about but got disappointed. I really didn't like the style. It was too melodramatic and pulling that many parallel stories was unnecessary. You can feel that it's trying too hard to be that epic book. And, I can't explain it, but it's so american. Now I feel reluctant to read anything else from Powers.