Uprooted – Naomi Novik

A dangerous and malevolent wood casts a deep shadow over the towns that border it, and by extension over the kingdom those towns belong to. Agniezska will soon be chosen, against all odds, by the Dragon, a reclusive wizard who protects the villages from the wood, at the cost of one girl every ten years. Her unexpected gift with magic will make her more of an actor in her kingdom’s fortunes than she could have imagined, or wanted.