ARALIACEAE (Ginseng Family)

Plants perennial, trees, shrubs, lianas, or herbs, sometimes with rhizomes. Leaves alternate (less commonly opposite or whorled in Hedera) or basal from rhizomes, simple or variously compound, petiolate, the petiole base often expanded and somewhat sheathing, the stipules partially fused to the petiole base or lacking. Inflorescences umbels of small flowers, these solitary or arranged into compound umbels, racemes, or panicles, usually with small, lanceolate bracts subtending the flowers and at the branch points. Flowers mostly perfect (functionally staminate or pistillate flowers sometimes mixed with the perfect ones), epigynous, actinomorphic. Sepals reduced to an inconspicuous crown or 5 small teeth, sometimes absent, when present usually persistent in fruit. Petals 5, often shed quickly after the flower opens. Stamens 5, the filaments free. Pistil 1 per flower, composed of 2–5 fused carpels, the ovary inferior with a nectar disk at the tip, the styles 1–5, sometimes slightly expanded at the base, persistent in fruit. Fruits berrylike drupes, with 1 stone per carpel. Sixty to 70 genera, 700–1,300 species, nearly cosmopolitan, most diverse in tropical portions of South America and Asia and Malesia.

Recent molecular and morphological phylogenetic studies (summarized in Judd et al., 1994, 2002) suggest that Apiaceae and Araliaceae might better be treated as a single family (under the name Apiaceae), but relationships among some groups of genera are still not clearly understood. Thus, the traditional classification as two separate families is followed in the present work. For further discussion, see the introductory portion of the Apiaceae treatment.

A number of species in the family are cultivated as ornamentals and/or used medicinally. Stem pith of the Asian species, Tetrapanax papyriferus (Hook.) K. Koch, is the source of rice paper (Graham, 1966).