Castor Beans and Castor Oil
Nature Bulletin No. 503-A October 20, 1973
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation
CASTOR BEANS AND CASTOR OIL
Young Americans of this generation seem to be growing up without
much personal experience with castor oil. We parents and
grandparents, however, still shudder at memories of times when, after
threats or promises, we made a face, closed our eyes, opened our
mouth and gulped great spoonfuls of the thick oily stuff. Today,
although more castor oil is produced than ever before, only a tiny
fraction of it is used as a laxative.
In temperate regions such as ours, the Castor Oil Plant or Castor Bean
is an annual up to 15 feet tall, a plant that grows anew from its seed
each year. Nothing is better for a fast-growing ornamental screen
about your home. In warmer climates it is a perennial, becoming a tree
30 or 40 feet tall. The leaves are very large, often 20 to 30 inches
across, deeply cleft and star-shaped with five to twelve points. The
clusters of flowers are followed by spiny capsules which, when ripe,
pop open to release three large glossy black or mottled seeds. The
Romans thought the castor bean seed looked like a blood-filled dog
tick, so they called it by the same Latin name, Ricinus.
Africa is supposed to be the original home of the wild castor bean. It
probably became a camp follower of man back in prehistoric times
when it grew without care about his dwellings long before its
usefulness was discovered. The ancient Egyptians valued its oil almost
as highly as that of the olive for their lamps. Over the ages, its
cultivation spread to many of the warmer countries of the Old World
and, then, to the New World. It escaped and now runs wild in
clearings, along roadsides and on dump heaps throughout the tropics
and subtropics. Both wild and cultivated castor beans are harvested by
the natives of many parts of the world. The unripe clusters of seed
capsules are spread on the ground until they dry, split open, and the
seeds fall out. Then they are winnowed by hand and sold or bartered,
often in very small quantities. The pomace, or cake remaining after the
oil is pressed out, is poisonous to livestock but can be used for
The total world crop of castor beans is about a billion pounds per year,
yielding half that poundage of castor oil. The principal producing
countries are India and Brazil with lesser amounts from other Latin-
American countries, the West Indies, Africa, other parts of Asia, and
the United States. American manufacturers use about 40 percent of the
world's crop and import nine-tenths of this. Castor Oil and its products
have hundreds of industrial uses and chemical research steadily adds
more. A substantial amount goes into paints, varnishes and lacquers.
A lipstick, a hair tonic, or a shampoo may contain over one-third
castor oil. Made into special lubricants for jet engines and racing cars,
it does not become stiff with cold nor unduly thin with heat. It is made
into plastics, soaps, waxes, hydraulic fluids and ink. During the war it
was stockpiled as a strategic material.
The Baker Castor Oil Company of New York is the largest
manufacturer in the industry and has been through most of its
hundred-year history. During the past ten years this company has
promoted the development of low-growing, high yielding castor
hybrids that produce a ton of beans to the acre; also special machinery
which allows the American grower to compete in the world market.
The 18,000 acres now planted to castor beans -- mostly in California,
Arizona and Oklahoma -- is triple that of last year and, soon, is
expected to reach 120,000 acres.
by moles in your lawn? Stick castor beans in their burrows.
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Update: June 2012