''Alisma plantago-aquatica'', also known as European water-plantain, common water-plantain or mad-dog weed, is a

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wid ...

flowering A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism ...

aquatic plant widespread across most of

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

and

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

, and apparently spread elsewhere in both the Old and

New World The term ''New World'' is often used to mean the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. ...

Description

''Alisma plantago-aquatica'' is a hairless plant that grows in shallow water, consists of a fibrous

root In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the su ...

, several basal long stemmed leaves long, and a triangular stem up to tall. It has branched

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

bearing numerous small

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s, across, with three round or slightly jagged, white or pale purple petals. The flowers open in the afternoon. There are three blunt green sepals and 6

stamens The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

per flower. The carpels often exist as a flat single whorl. It flowers from June until August. The fruits appear as a ring of seeds inside each flower.

Chemistry

Chemical constituents of —rhizomes of ''Alisma orientale'' (syn. ''Alisma '' var. ''orientale'') as a traditional Chinese medicine—include alisol A 24-acetate and alisol B 23-acetate. The content of these two compounds are significantly different in of different areas.

Similar species

Narrow-leaved water plantain '' Alisma lanceolatum'' differs only in that the leaf tips are

acuminate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular ...

and shape is narrow

lanceolate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular ...

. According to some sources, presumed specimens found in North America are actually the similar '' A. subcordatum'' and '' A. trivale''.

Taxonomy

The word ''alisma'' is said to be a word of Celtic origin meaning "water", a reference to the habitat in which it grows. Early botanists named it after the ''

Plantago ''Plantago'' is a genus of about 200 species of flowering plants in the family Plantaginaceae, commonly called plantains or fleaworts. The common name plantain is shared with the unrelated cooking plantain. Most are herbaceous plants, though ...

'' because of the similarity of their leaves.

Distribution and habitat

The species is widespread across most of

and

from

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

and

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria t ...

to Japan,

Kamchatka The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and west ...

and

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

. It is also regarded as native in northern and central

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

as far south as

Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands ...

, and in Australia. It is reportedly naturalized in

southern Africa Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number o ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

Washington state Washington (), officially the State of Washington, is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the Washington ...

and

Connecticut Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York to the west, and Long Island Sound to the south. Its capita ...

. Some sources maintain that the species is widespread across North America, but these reports appear to have been based on misidentified specimens. It is found on mud or in fresh waters.

Uses

The rootstocks contain starch and can be boiled or soaked to remove bitterness before eating. Aquatic plants in general should be cooked before consumption to kill parasites. According to ''Flora of the U.S.S.R.'' (1934), "A powder prepared from dried roots is used in popular medicine as a cure for

rabies Rabies is a viral disease that causes encephalitis in humans and other mammals. Early symptoms can include fever and tingling at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, ...

and crushed leaves are used against mammary congestion; fresh leaves are employed in homeopathy.'' ''... Since this species is often confounded or identified with others of the genus, the reported data may also refer to 'A. orientale'' or ''A. lanceolatum''" ''A. '' is also known as ''mad-dog weed'', as if it could be used to cure rabies, but should not be confused with '' Scutellaria lateriflora'' (mad-dog skullcap), which is also sometimes called ''mad-dog weed''. ''Alisma orientale'' is sometimes treated as a variety of this species (''A. '' var. ''orientale''). The rhizomes of ''A. orientale'' have been used as a

traditional Chinese medicine Traditional Chinese medicine (TCM) is an alternative medical practice drawn from traditional medicine in China. It has been described as "fraught with pseudoscience", with the majority of its treatments having no logical mechanism of acti ...

, ''ze xie''. However, it may have serious side effects or even toxic effects such as

hepatotoxicity Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdrawn fr ...

in patients with chronic hepatitis'' ''B.

References

External links

line drawing from Flora of Pakistan, ''Alisma plantago-aquatica''photo of herbarium specimen at Missouri Botanical Garden, collected in Ethiopia (Abyssinia) in 1898Kew Royal Botanic Gardens, London, Alisma plantago-aquatica (common water-plantain)Le Jardin du Pic Vert, Plantain d'eau, Alisma plantago-aquaticaTela Botanica, Alisma plantain d'eauNatureGate, Luontoportti, Helsinki, Water-plantainAltervista Flora Italiana, Piantaggine acquaticaRoyal Horticultural Society
{{taxonbar, from=Q21063 plantago-aquatica Flora of Africa Flora of Asia Flora of Australia Flora of Central Asia Flora of China Flora of Europe Flora of Gabon Flora of Kosovo Flora of New Zealand Flora of Russia Flora of Siberia Freshwater plants Medicinal plants of Europe Medicinal plants of North America Plants described in 1753 Plants used in traditional Chinese medicine Taxa named by Carl Linnaeus