I think that when three of the main characters are aged from twelve to sixteen throughout two thirds of the book, it necessarily takes on this genre. They need to be interested in the doings of, and speak in the voice of, people of that age. Their thoughts and speech must be age appropriate, which doesn't mean that you talk down to them. They sometimes surprise you with their concerns.
Don't you think there's something almost mystical about trees? No? It's just me, then? They are the largest living things you will come aross in your daily life. What's going on in there?
As well as the three young people, Sylvie, her brother Gregor and their cousin Erik, trees are the main stars of the show in this book. I've very much enjoyed writing it. I'll tell you more soon, and maybe show you the cover.