Acorus calamus


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Acorus calamus
Species Authority: L.
Common Name/s:
English Sweet Flag
Calamus aromaticus Garsault.
Taxonomic Notes: Considerable confusion exists in the taxonomic literature over the status of Acorus in North America. Whether Acorus is native or introduced, as well as the number of taxa in North America, has been debated for years. Evidence based on studies of morphology, essential oil chemistry, cytology, isozymes, and ethnobotany supports the existence of two species in North America; A. calamus, an introduced sterile triploid, and A. americanus, a native fertile diploid. A. americanus is not only morphologically distinct from triploid A. calamus but also from diploid and tetraploid A. calamus populations occurring in Asia (Thompson 2002).

In this assessment, the distinction is not recognised.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2011
Date Assessed: 2011-08-04
Assessor/s: Gupta, A.K.
Reviewer/s: Allen, D. & Lansdown, R.V.
The species is widespread and is tolerant to water pollution and is suggested to be used to clarify polluted water. It is assessed as Least Concern.

Geographic Range [top]

Range Description: Widespread in Asia (including throughout southern China, Europe, North America, and Russia (Far East, Siberia) (eFloras 2011).
Bangladesh; Cambodia; Canada (Alberta, British Columbia, Manitoba); China (Guangdong, Guangxi, Guizhou, Xinjiang, Yunnan); Hong Kong; India; Japan; Kazakhstan; Korea, Democratic People's Republic of; Korea, Republic of; Lao People's Democratic Republic; Malaysia (Peninsular Malaysia, Sarawak); Mexico; Mongolia; Myanmar; Nepal; Philippines; Russian Federation (Altay, Amur, Buryatiya, Chita, Irkutsk, Krasnoyarsk, Kuril Is., Primoryi, Sakhalin, Tuva, West Siberia); Sri Lanka; Thailand; United States (Alaska); Uzbekistan; Viet Nam
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: The wild populations of the Pearl River region in China are small.
Population Trend: Unknown

Habitat and Ecology [top]

Habitat and Ecology: The species grows on the margins of standing or slow-flowing water, typically occur in river backwaters, canal margins and the margins of ponds and lakes, swamps, pond sides, standing water, and also cultivated.
Systems: Terrestrial; Freshwater

Threats [top]

Major Threat(s): No information is available on threats to the species or its habitats.

Conservation Actions [top]

Conservation Actions: No conservation measures have been undertaken specifically for this species and none are needed.
Citation: Gupta, A.K. 2011. Acorus calamus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <>. Downloaded on 19 April 2014.
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