Common names (selected): English: African coffee tree, castor, castor bean, castor bean plant, castor oil bush, castor oil, castor oil plant, castor oil tree, castorbean tree, castor-oil plant, maple weed, Palma Christi, Palma-christi, wonder tree; Chinese: 蓖麻 (ramie); Fijian: belenivavalagi, mbele ni vavalagi, utouto; French: grande epurge, ricin, ricin commun, huile montecristi, huile ricin, mascarite, mascristi, palma cristi (Haiti); German: Rizinus; Hawaiian: la'au 'aila, ka'apeha; Maori: pakarana, tuitui papa'a, tuitui; Philippines: tangan-tangan; Portuguese (Brazil): carrapateiro, carrapato, catapucia-maior, caturra, mamona, mamoneira, palma-de-cristo, rícino, tortago mamoeiro; Samoan: lama palagi, lama palagi; Spanish: carrapa, higuereta, palma Christi, ricino verde (Cuba), higuerilla, palmacristi (Mexico), hierba mora, higuera del diablo, ricino, ricino comun, tartago; Sri Lanka: amanaku maram; Thai: lahung; mahung; Vietnamese: daudan; thâu dâù

Description: Perennial shrub

Native range and distribution: R. communis is probably native to North-Eastern Africa and the Middle East. Currently, populations can be found across the African continent. It is widely naturalized across the world, including in the U.S., Mexico, South America, Australia, New Zealand and on numerous Pacific islands.

Urban habitat: R. communis frequently thrives in riparian areas and in abandoned fields, drainages, ditches, and along roadsides and railroad tracks. 

Ecological function: Food for ants, who disperse the seeds and assist with their germination process.

History / human uses: Known as 'castor beans', the seeds of R. communis are among the most infamous in the world. Its genus name comes from the Latin word ricinus meaning ‘tick’ from the appearance of the seeds. The plant was cultivated for the oil produced from its seed in Egypt as long as 6000 years ago. In the U.S., the species was first documented in Florida in the 1760s and by 1819 it is listed as naturalized in Hawaii. All over the world, the traditional use of its oil has been for illumination and medicine. The oil is a well-known laxative that has been widely used for over 2,000 years. In China, the oil is used in traditional medicine for internal use or externally in dressings. The oil is also found to have an antidandruff effect and is sometimes used as a vehicle for medicinal and cosmetic preparations. Castor oil gel is useful in the treatment of non-inflammatory skin diseases and is a good protective in cases of occupational eczema and dermatitis. From World War I until the 1960s, its oil was utilized as a lubricant for aircraft, but the U.S. also began using its seed to develop biological warfare agents to produce ‘ricin’, as the toxin in the seed is called, which ranks among the most poisonous substances found in nature. By World War II the U.S., collaborating with the British, developed but never implemented in combat, a ricin-containing bomb code-named ''compound W.'' The 1978 assassination of the Bulgarian defector Georgi Markov was said to have been caused by an injection into his thigh of a small metal pellet containing ricin by a weapon disguised as an umbrella. Its oil has also been used as a tool of torture: force-feeding castor oil to prisoners was practiced by the Nationalists under the leadership of Francisco Franco during the Spanish Civil War and in Mussolini’s fascist Italy, the paramilitary Blackshirts used castor oil for the same purpose to deal with its opponents. The severe diarrhea brought on by the ingestion of large amounts of castor oil leads to dehydration which could ultimately cause death. Castor oil is also used in the manufacturing of paints, dyes, adhesives, inks, soaps, cosmetics, chocolate, hydraulic brake fluids, plastics, waxes, varnishes, sealants and synthetic resins. A fibre for making ropes is obtained from the stems. The growing plant is said to repel flies and mosquitoes. Cellulose from the stems is used for making cardboard and paper. R. communis is also sometimes planted as an ornamental.