Pokeweed (Phytolacca americana) is a robust perennial potherb native to the eastern United States. It belongs to the pokeweed family (Phytolaccaceae), a small family found mostly in Africa and the New World. In addition to pokeweed, it also includes several enormous South American trees and some unusual serpentine vines of the tropics. Poke is derived from the Algonquian Indian word "pakon" or "puccoon," referring to a dye plant used for staining. It is sometimes spelled polk and the leaves were reportedly worn by enthusiastic supporters during the campaign of James K. Polk, 11th president of the United States. The generic name Phytolacca is derived from the Greek word phyton (plant) and the French lac (lake--a dark red pigment), referring to the crimson juice of ripe berries. Pokeweed may grow to nine feet tall, with large, alternate leaves and a carrotlike taproot. It may become a very invasive weed in southern California gardens and is difficult to eradicate when it becomes well-established. Greenish-white flowers are produced in long clusters (racemes) that droop due to the weight of ripening fruit. The flattened berries change from green to shiny purplish-black. Ripe berries yield a crimson juice that was used as a substitute for red ink and to enhance the color of pale wines. The coloring of wine with pokeweed berries has been discouraged because they are very poisonous.

Freshly cut young leaves and shoots may be cooked and eaten like spinach. They should be boiled twice, and the first water being discarded. In 1969, when astronaut Neil Armstrong walked on the moon, a popular song on the radio was "Poke Salad Annie." Some versions were spelled "Polk Salad Anne." The song depicted a poor southern girl who picked a wild plant called pokeweed for a vegetable. The greens are also called poke salet, and they are sometimes canned and sold in markets.

Of all the species of Phytolacca, the most remarkable is the ombu tree (P. dioica) of the Argentine pampas. Ombu trees (also called umbu trees) grow to a height and spread of 60 feet (20 m) or more, often with multiple trunks developing from an enormous base resembling a giant pedestal. The huge base may be three to six feet tall (1-2 meters) and 95 feet (30 meters) in circumference.

Photo by Tony Rodd licensed under CC BY-NC-SA 2.0

This tree is sometimes called a giant "herb" because it doesn't have a solid, woody trunk with hard, lignified growth rings. Its trunk consists of anomalous secondary thickening rather than true wood. As a result, the ombu grows fast but its wood is soft and spongy. The trunks store water and have structural integrity due to turgor pressure. When dry, the trunk resembles concentric layers of cardboard. True wood is composed of densely packed dead xylem cells with lignified secondary cell walls. Left: A cross section of an ombu limb showing harder (more resistant) xylem tissues separated by spongy parenchyma that has since disintegrated.

Ombu trees are native to the grassy pampas of Argentina, usually widely spaced and the only trees for miles. They are called "lighthouses of the pampas" by gauchos who use them for welcome landmarks and shelters. The massive, fire-resistant trunk contains water storage tissue, an excellent adaptation for raging grass fires that periodically sweep across the pampas. Even young trees develop the characteristic enlarged (caudiciform) base, an obvious advantage in surviving prolonged months of drought during the dry season.

Several specimens of ombu trees were planted at the Palomar College Arboretum, including another interesting species from Peru (P. weberbaueri) and an unusual hybrid between the two species. The leaves have natural insecticidal properties and many years ago a professor of veterinary medicine (possibly from Cornell University) stopped by Palomar College to collect leaves for his research. He apparently located our trees on Wayne's Word, but unfortunately, I cannot find my details of his visit.

The North American pokeweed (Phytolacca americana) is synoecious, a term applied to a plant (or a species) in which the flowers are perfect (bisexual) with male stamens (androecium) and female pistil (gynoecium). Some references state that flowers of Phytolacca may also be unisexual, in which case, the species can be dioecious. Although the specific epithet for the umbu tree is dioica, plants I examined in the Palomar College Arboretum had bisexual flowers, with stamens (androecium) and a pistil (gynoecium). Racemes in fruit were sometimes lacking evidence of stamens. In some flowers with mature stamens the gynoecium was not fully developed. According to the scholarly textbook Plant Ststematics: A Phylogenetic Approach by W.S. Judd, et al. (2008), the flowers of Phytolaccaceae are usually bisexual.

The pokeweed family also includes some unusual tropical vines, mostly native to the Caribbean region, Central and South America. Agdestis clematidea is a climbing vine native to Mexico and Guatemala. It grows from a huge gray tuber weighing up to 150 pounds (68 kg) and resembling a large granite boulder. Another interesting species called hoop vine (Trichostigma octandrum) in native to the Virgin Islands. Like a woody boa constrictor, it trails along the forest floor, ascending tropical trees and often forming tangled masses of writhing serpentine branches. It is essentially leafless except on new growth where leaves are produced that superficially resemble pokeweed. Hoop vine is used in basketry on the island of St. John, a rare art that is only practiced today by a few native islanders. The tightly woven baskets are made entirely from strips of hoop vine and are masterful works of art.

Return To Economic Plant Families Page Return To WAYNE'S WORD Home Page Return To NOTEWORTHY PLANTS Page Go To Biology GEE WHIZ TRIVIA Page Go To The LEMNACEAE ON-LINE Page