Shadows of the redwood

Sixteen-year-old half-elf Keelie, her cat Knot, and her grandmother, also an elf, travel to California to help a redwood forest that is missing its tree shepherd, and with the help of the handsome Sean and a former apprentice of her father's, plus a mysterious coyote, Keelie tries to discover the deadly secret of the bloodroot tree in time to save the forest.