Tanoak Tanbark-oak

Notholithocarpus densiflorus (Fagaceae), formerly Lithocarpus densiflorus, is a broadleaf evergreen tree native to southwestern Oregon and California. It can reach 130 feet in its native range, with a conical to rounded crown and large horizontal branches. Thick, leathery leaves are persistent. White male catkins turn rust-colored and have an unpleasant odor. Acorns develop in bristly cups and take two years to mature.

Tanoak grows in full sun to part shade and is very shade tolerant. It performs best in rich, moist soil but tolerates some drought once established. The species is highly susceptible to sudden oak death (Phytophthora ramorum) and Armillaria root rot. The bark has high tannin content and was historically important for leather tanning. Acorns were a staple food for indigenous peoples of California and southern Oregon after leaching to remove tannins. Hardy in Zones 7a to 8b.