''Stratiotes aloides'', commonly known as water soldiers or water pineapple, is a submerged

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

native to

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and northwestern

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 area ...

. In Britain it was once common in East Anglia and still is in many places, particularly wet ditches and healthy ponds. It is the only species in the genus

Stratiotes ''Stratiotes'' is a genus of submerged aquatic plant commonly known as water soldiers, described as a genus by Linnaeus in 1753. Several specific names have been coined within the genus, but at present only one is recognized: '' Stratiotes aloi ...

Invasive species

''Stratiotes aloides'' has been found in the Trent River in eastern

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

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Description

''Stratiotes aloides'' has a rosette of serrated

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

, lanceolate, up to 30 cm long in tufts. White

flowers 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 ...

are up to 45 mm across with many stamens in the male plants are produced in the summer.Parnell, J. and Curtis, T. 2012.'' Webb's An Irish Flora'' Cork University press.

Ecological aspects

In the summer this plant floats on the water surface with the

just above the surface. In the autumn they become covered with a slimy secretion (calcium carbonate) and the whole plant sinks to the bottom to rise again in the spring. Fossils have been found of this plant. Plants are dioecious, male and female plants must be grown if seed is required. Only the female plant occurs naturally in Britain, though plants with hermaphrodite flowers are also found occasionally. Seed is never set in Britain, the plants increasing mainly by offsets.

Distribution

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

, it is found in shallow waters where it was introduced. Apparently now extinct in the north-east of Ireland. Rare in east England.

Cultivation

Most suitable for the cool

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

pond A pond is an area filled with water, either natural or artificial, that is smaller than a lake. Defining them to be less than in area, less than deep, and with less than 30% emergent vegetation helps in distinguishing their ecology from th ...

. Propagation from runners which form from the centre of the rosette of

. The herb has had a high reputation for treating wounds, especially when these are made by an iron implement. It is applied externally. The plant is also said to be of use in the treatment of St. Anthony's fire and also of bruised kidneys.Grieve, ''A Modern Herbal''. Penguin (1984)

References

* Clapham, Tootin and Warburg. ''Flora of the British Isles''. Cambridge University Press 1962

External links

IOW Fishkeepers

Plants for a Future
{{Taxonbar, from=Q162030 Hydrocharitaceae Freshwater plants Plants described in 1753 Taxa named by Carl Linnaeus