This was once a common tree but in recent years its population has been devastated by Sudden Oak Death. Sometimes shrubby and many-stemmed but often a tall single-trunked tree. It has distinctive leaves, evergreen, simple, alternate, ovate to oblong, 3–14 cm long with an obtuse tip and margins that are either entire or serrated. The tree is monoecious, the tiny white male flowers in more or less erect catkin-like spikes and the inconspicuous female flowers below the male. Like most black oaks, the acorns mature over two years. The acorns are distinctive, the cup having a soft-spiny appearance, the result of very slender, spreading to reflexed scales quite different from the appressed scales found in true oaks.