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Sweet Flag

by Karyn Siegel-Maier


Calamus (Acorus americanus, previously A. calamus), commonly known as sweet flag, has been an item of trade by various cultures since biblical times. In the Orient, and in ancient Egypt, the rhizome was thought to be a powerful aphrodisiac, while the Turk's carried the aromatic rhizome to thwart infectious disease. The Sanskrit Kalamas, the Roman calamus and the Greek Kalamos all refer to the reed of the plant.


The herb was introduced to Russia sometime in the 11th century by the Mongolian Tartars. Sweet flag didn't become popular in Europe until the Viennese botanist, Clusius, brought it back with him from Asia Minor and later shared the rhizomes with botanists of neighboring countries. The leaves are well known for their lemon-like scent and in England, calamus became a popular strewing herb. Many cathedrals have preserved this tradition well into the 20th century.

In the 17th century, sweet flag was much in demand, so much so that over harvesting eventually led to its near eradication. Sweet flag was heavily used by perfumers and makers of powdered wigs. Dutch children were given the rhizomes as a form of chewing gum or as a crystallized candy. The Benedictine and Chartreuse liqueurs were flavored with the herb, as well as many liqueurs, beers, bitters, tonics and gin as late as the 1960's. The famous Stockton bitters include calamus. Sweet flag was also once used in toothpowders. Remember the dry shampoos of the 1960's and early 1970's? You guessed it - they contained dried, ground calamus root.


Indigenous to the wetlands of North America, sweet flag was an important medicinal plant to the Plains Indians for respiratory disorders. The Shakers also adopted the herb into their medicinals to treat coughs, bronchial congestion and toothache. Today, Chinese herbalists often recommend calamus to lower blood pressure and to treat epilepsy. In India, it is used to check asthma. Some modern herbalists report its effectiveness in treating eating disorders, including the lack of appetite associated with cancer or other serious illnesses.


There are doubts about the safety of sweet flag however. The European and American species have a relatively low toxicity, at least according to some studies done in the 1980's. But previous studies on the Indian, or "Jammu" variety, revealed the carcinogenic effects of B-asarone. Rats, who were fed varying concentrations of calamus oil ranging from 500 to 5,000 parts per million, developed abnormalities of the heart and liver after 18 weeks, and malignant intestinal tumors after 59. Although the European and American species are void of B-asarone, the FDA banned all calamus extracts from use in foodstuffs.


Gardeners should take note, however, that Indian calamus effectively kills ants and fleas when applied as a fine dust. It is also very efficient at getting rid of grain weevils since it renders the male sterile. While the flowers of this herb are not particularly attractive, the stems or reeds are rather interesting looking and quite aromatic. A moist area in shade or woods, especially near a stream or pond, makes the ideal habitat for cultivation.



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