[Kath]

But surely if Treebeard did care for the trees and was active in his role as shepherd or caretaker, he would already know about the trees that had been cut down? His words about the orcs (as Boromir said) semm to show he is aware that this is happening, so for him to be suddenly so surprised by it is odd. It's almost as though he's been backed into a corner and only now that he can't argue his way out of it does he agree to fight.