" Ours is only a little power, seems like, next to theirs," Moss said. "But it goes down deep. It's all roots. It's like an old blackberry thicket. And a wizard's power's like a fir tree, maybe, great and tall and grand, but it'll blow right down in a storm. Nothing kills a blackberry bramble. "

― Ursula K. Le Guin , Tehanu (Earthsea Cycle, #4)