Shrubs or trees with alternate leaves that can be evergreen or deciduous. Plants may have separate male and female individuals (dioecious) or both sexes on one plant (monoecious). Pollen cones appear alone or in clusters on the stem tips or leaf axils and mature annually. Seed cones also appear singly on the stem tips or leaf axils, maturing in 1–2 years during the fall, and often remain on the plant for several more years.