Description

Shrub growing to 6½ ft (2 m). Has fleshy roots, woody stems, large palm-shaped leaves, and green flowers.

Habitat & Cultivation

Cassava is native to tropical Central and South America. Possibly the most grown root crop in the world, bitter and sweet varieties are grown commercially throughout the tropics (Nigeria, Thailand, and Brazil being the foremost producers). The plant was first cultivated in Peru around 4,000 years ago. The root is unearthed 8 to 24 months after planting.

Part Used

Root.

Constituents

Cassava contains cyanogenic glycosides (0.02–0.03% in the bitter varieties, 0.007% in the sweet) and starch.

History & Folklore

Bitter cassava has large quantities of highly toxic glycosides, and must be carefully soaked and cooked before it is safe to eat. (Sweet cassava is safe to eat without such processing.) Tapioca is a native Brazilian name for the processed root, which is used in commercial food preparation as a thickening agent. The Witoto of the Colombian Amazon poison fish with the water used to wash bitter cassava. The Makuna use the wash water to treat scabies.

Medicinal Actions & Uses

Cassava root is easily digestible and makes a suitable, if low-protein, food for convalescence. The bitter variety may be used to treat scabies, diarrhea, and dysentery. Cassava flour may be used to help dry weeping skin. In China, a poultice is made of cassava, wheat flour, and ginger (Zingiber officinale) to draw out pus when infection is present.

Caution

Raw bitter cassava is toxic and has caused many deaths. The root must be carefully soaked and cooked before eating.