A very large deciduous tree with a vase-shaped to rounded form. Branches are arching, spreading, contorted and twisting. Bark becomes checked, fissured and dark gray with age. Dark green leaves are leathery and oval with deep, rounded lobes. Foliage turns yellow in fall. Inconspicuous female flowers and male catkins yield acorns. Native to valleys of California. Provides habitat and food for numerous animal species.