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

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

flowering Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

aquatic plant Aquatic plants, also referred to as hydrophytes, are vascular plants and Non-vascular plant, non-vascular plants that have adapted to live in aquatic ecosystem, aquatic environments (marine ecosystem, saltwater or freshwater ecosystem, freshwater ...

widespread across most of

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

, and apparently spread elsewhere in both the Old and

New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...

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 plant organ, 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 bel ...

, several basal long stemmed

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

long, and a triangular

stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...

up to tall. It has branched

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

bearing numerous small

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

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 A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

and six

stamens The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

per flower. The

carpels Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ...

often exist as a flat single

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagra ...

. 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 ''Alisma lanceolatum'' is a species of aquatic plant in the water plantain family known by the common names lanceleaf water plantain and narrow-leaved water plantain. It is widespread across Europe, North Africa and temperate Asia. It is natural ...

'' differs only in that the leaf tips are

acuminate The following terms are used to describe leaf plant morphology, morphology in the description and taxonomy (biology), taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade ...

and shape is narrow

lanceolate The following terms are used to describe leaf plant morphology, morphology in the description and taxonomy (biology), taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade ...

. According to some sources, presumed specimens found in

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

are actually the similar '' A. subcordatum'' and '' A. trivale''.

Taxonomy

The word ''alisma'' is said to be a word of

Celtic Celtic, Celtics or Keltic may refer to: Language and ethnicity *pertaining to Celts, a collection of Indo-European peoples in Europe and Anatolia **Celts (modern) *Celtic languages **Proto-Celtic language *Celtic music *Celtic nations Sports Foot ...

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 a ...

'' 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, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...

and

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

Kamchatka The Kamchatka Peninsula (, ) 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 western coastlines, respectively. Immediately offshore along the Pacific ...

and

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

. 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. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

as far south as

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

, and in

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

. It is reportedly naturalized in

southern Africa Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

Washington state Washington, officially the State of Washington, is a state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from the national capital, both named after George Washington ...

and

Connecticut Connecticut ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the south. ...

. 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 Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diet ...

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. It was historically referred to as hydrophobia ("fear of water") because its victims panic when offered liquids to drink. Early symptoms can include fever and abn ...

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 ''Scutellaria lateriflora'', (commonly "blue skullcap", "mad dog skullcap",traditional Chinese medicine Traditional Chinese medicine (TCM) is an alternative medicine, alternative medical practice drawn from traditional medicine in China. A large share of its claims are pseudoscientific, with the majority of treatments having no robust evidence ...

, ''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 (DILI) is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdr ...

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 Flora of Portugal 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