The growth habit is typically erect and self-supporting, but epiphytic and climbing habits are recorded. In those, the juvenile individual begins as an epiphyte and sends roots down to the ground to establish itself as a separate tree. Stomata are generally confined to the abaxial surface and cyclocytic. An adaxial hypodermis is present, the mesophyll contains sclerencymatous idioblasts, and minor leaf veins are without phloem transfer cells. The individual flowers are arranged in open, racemose to paniculate inflorescences which are borne either terminal or axillary on branchlets.
Flowers are sexually dimorphic.
The staminate flowers have a campanulate hypanthium and are always petaliferous. The petals are yellow to greenish-yellow, reflexed at anthesis, and quickly caducous. Anthers are opposite the sepals and alternating with the petals. The pistillate flowers in a few species do not develop petals. The epigynous disc is not unlike those found in Araliaceae.