sixteenth century England, and the plant was commonly spread 
on the floors of homes in colonial New England. The identifying 
scent has been helpful in distinguishing it from the poisonous 
Blue Flag (Jris versicolor L.). a marshy plant that resembles 
Sweet Flag in its vegetative stage. 
The plant’s widespread use among peoples of both the Old 
and New World is due partly to its cosmopolitan range in the 
Northern Hemisphere on the continents of Asia, Europe and 
North America. Although Acorus Calamus is a gregarious semi- 
aquatic plant restricted in habitat to the margins of fresh and 
brackish waters—swamps, marshes, bogs, ponds and rivers—it 
is able to live in a variety of climatic zones ranging from the 
tropics to the sub-arctic. The plant grows most abundantly, 
however, in the North Temperate Zone. 
Man has increased the geographic range of Acorus Calamus. 
It was not native to Europe. European populations of Acorus 
Calamus do not bear fertile fruit: they remain sterile triploids 
(2n = 36) and propagate vegetatively by rhizomes. The nomadic 
Tartars had introduced the plant into European Russia by the 
thirteenth century (Buell, 1935); the “Mongolian Dragon” also 
introduced the plant into eastern Europe (Buell, 1935). Accord- 
ing to Murray Buell, Tartars brought Acorus Calamus on the 
steppes of Russia because they drank water only when macer- 
ated with the rhizomes (Buell, 1935). Rhizomes were also 
introduced from southern Asia via Constantinople (Istanbul) 
into central Europe during the mid-sixteenth century (Mucke, 
1908). 
Most populations of Acorus Calamus east of the Appalachi- 
ans are sterile. Some authorities believe that early seventeenth 
century colonists introduced it to the eastern seaboard from 
Europe. Experiments have shown that some populations in the 
Northeast are able to reproduce by seed; sterile clones may have 
resulted from selected rhizomes planted by colonists for medi- 
cinal and confectionary uses (Jervis and Buell, 1964). Possibly, 
the species is represented by both native and introduced strains 
along the Atlantic seaboard. 
Populations of Sweet Flag in the interior of North America 
are fertile diploids (2n = 24), but Melvine R. Gilmore, a noted 
ethnobotanist, was unsuccessful in finding seed-producing 
236 
