Of interest this week at Beal...

Castorbean Ricinus communis Family: the Spurge family, Euphorbiaceae Also called Palm-of-Christ, Palma Christi W. J. Beal Botanical Garden The genus name Ricinus makes use of the Latin word for tick. It is derived from the resemblance of the ripe seed to an engorged female tick. In fact ricinus is the species epithet applied to the Mediterranean sheep tick, Ixodes ricinus.

Some think that the term castorbean comes from its reputation as yielding a replace- ment for castoreum, a perfume base derived from the perineal glands of the beaver, Castor canadensis. It is nutritious castor oil that most associate with the production of castorbean. Castorbean, Ricinus communis, is not actually related to the true bean family (Fabaceae) but is in the euphorbia or spurge family (Euphorbiaceae) most com- monly known for its commercial holiday member, the Christmas poinsettia, Euphorbia pulcherrima.

In the modern world of terrorism and intrigue, the toxin of castorbean has become momentarily well-known. Ricin, a large complex protein found in small amounts throughout the plant, but in more significant amounts in the seed coat, is a very pow- erful toxin. It is capable of producing human fatality in amounts of about 1 milligram.

It is the reason that any ingestion of raw seeds is a serious clinical dose for humans or animals alike.

In February, 2008, a man staying at an extended residence hotel in Las Vegas, Nevada was found in respiratory distress in the company of a small amount of ricin. One of the dogs sharing the room was a ricin fatality when all was done. News accounts say the source and the purpose of the ricin was unknown, but the event served to underscore the potential importance of such a virulent compound.

The oil production of castorbean has lead to its increased production as a biofuel pos- sibility. But it is commonly grown as a garden accent plant in the temperate zones, where it is treated as an annual. It is perennial in the tropics, and most commercial The highly ornamented coat of the castorbean gives the plant its resemblance, by seeds, to ticks. It is this seed coat that also harbors the main stock of ricin, the fantastically toxic protein that makes the raw seeds so dangerous. The seeds also produce castor oil.

production of it takes place there. It has been used as a medicinal plant in the Asian and Ayuvedic traditions for centuries, and its undecylenic acid component has been demonstrated to have antifungal potential.

This striking plant can reach 3 meters (10 feet) in height as an annual if started indoors early in the season. The leaves that are palmately lobed may reach over two feet in width. The striking red stigmas identify the female flowers (far right photo on previous page) that ripen into fruits with either spiky red or smooth green (ours) exteriors.