Phytolacca is a genus of perennial flowering plants in the family Phytolaccaceae, order Caryophyllales, comprising approximately 25 to 35 species of herbs, shrubs, and trees. The genus is native to North America, South America, and East Asia and is present on every continent except Antarctica, having been introduced to Europe and Australasia.
Plants range from 1 to 25 metres tall. They bear alternate, simple leaves with entire or crinkled margins, tapering to a point, and the leaves may be either deciduous or evergreen depending on the species. Stems are characteristically green, pink, or red. The flowers are small, greenish-white to pink, and arranged in long terminal racemes. They develop into globose berries 4 to 12 millimetres in diameter, green at first and ripening to dark purple or black.
Many species are known as pokeweeds, pokeberry, pokeroot, inkberry, or poke sallet. The genus contains the compounds phytolaccatoxin and phytolaccagenin, which are toxic to mammals and present in the leaves, stems, roots, flowers, and berries of many species. Birds are not affected by the toxin and consume the berries widely, passing the hard-shelled seeds intact — a key mechanism of seed dispersal.
Notable members include Phytolacca americana (American pokeweed), the most familiar North American species, and Phytolacca dioica (ombú), a tree-forming species of the South American pampas that serves as a cultural symbol in Uruguay and Argentina.
Etymology
The generic name Phytolacca combines the Greek φυτόν (phyton), meaning "plant," with the Latin lacca, a red dye — a reference to the deep red-purple pigment produced by the berries of many species in the genus.
Distribution
Phytolacca is native to North America, South America, and East Asia, and members of the genus have naturalized on every continent except Antarctica. The genus is introduced in Europe and Australasia. In the Pacific Northwest of North America, pokeweed is considered an invasive species.
Ecology
The berries of Phytolacca are consumed by birds and box turtles, which serve as primary dispersers; the hard-coated seeds pass through the digestive system intact. The ombú (Phytolacca dioica) grows to tree stature on the open pampas of South America, where it functions as one of the few sources of shade; its massively buttressed trunk, soft water-storing wood, and deep root system make it resistant to both grass fires and drought. Phytolacca weberbaueri from Peru similarly attains tree size.
Cultural Uses
Phytolacca americana (American pokeweed) has a long history of use as both folk medicine and food in the southern United States, where young shoots are prepared as "poke salat." Because all parts of the plant are toxic to mammals, traditional preparation involves boiling the greens three times in successive changes of water to reduce harmful constituents; the root is never eaten. The berries have historically been used as a source of red-purple ink and dye, consistent with the genus's Latin name lacca.
