''Equisetum variegatum'', commonly known as variegated horsetail or variegated scouring rush, is a species of

vascular plant Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They ...

in the

horsetail ''Equisetum'' (; horsetail, snake grass, puzzlegrass) is the only living genus in Equisetaceae, a family of ferns, which reproduce by spores rather than seeds. ''Equisetum'' is a " living fossil", the only living genus of the entire subclass ...

family Equisetaceae. It is native to the Northern Hemisphere where it has a circumpolar distribution.

Description

It is a variable species with several

ecotype In evolutionary ecology, an ecotype,Greek: ''οίκος'' = home and ''τύπος'' = type, coined by Göte Turesson in 1922 sometimes called ecospecies, describes a genetically distinct geographic variety, population, or race within a specie ...

s, some of which are distinct subspecies. The stems can grow to 40 cm (occasionally 80 cm) in height but are often much smaller. Some forms have prostrate stems that creep along the ground while other forms grow more erect. The stems are dark blue-green, slender and rough to the touch. They may be unbranched or have branches growing from the base. The stem nodes are covered with a sheath that is marked with a black band and has dark teeth with white edges. The stems are tipped with a small cone, 3–4 mm across, which is usually green with a black, bluntly-pointed tip.

Distribution and habitat

It has a circumpolar distribution in the northern hemisphere, where it is occurs in northern

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 enti ...

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 ...

and North America including

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is ...

Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its ...

and the

Faroe Islands The Faroe Islands ( ), or simply the Faroes ( fo, Føroyar ; da, Færøerne ), are a North Atlantic archipelago, island group and an autonomous territory of the Danish Realm, Kingdom of Denmark. They are located north-northwest of Scotlan ...

. Its range extends south as far as the

Pyrenees The Pyrenees (; es, Pirineos ; french: Pyrénées ; ca, Pirineu ; eu, Pirinioak ; oc, Pirenèus ; an, Pirineus) is a mountain range straddling the border of France and Spain. It extends nearly from its union with the Cantabrian Mountains to ...

and

Apennines The Apennines or Apennine Mountains (; grc-gre, links=no, Ἀπέννινα ὄρη or Ἀπέννινον ὄρος; la, Appenninus or – a singular with plural meaning;''Apenninus'' (Greek or ) has the form of an adjective, which wou ...

in Europe,

Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 millio ...

and Japan in Asia 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 cap ...

Wisconsin Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...

and

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idah ...

in North America. It prefers open, lime-rich sites, often those that flood in winter. It occurs in

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, fl ...

slacks, mountain flushes and beside lakes, rivers and canals.

References

*Flora of North America
''Equisetum variegatum''
Accessed 30 July 2008. *Hutchinson, G. (1996) ''Welsh Ferns'', National Museums and Galleries of Wales. *Page C. N. (1982) ''The Ferns of Britain and Ireland'', Cambridge University Press. *Preston, C. D. & Pearman, D. A. (2002) ''New Atlas of the British and Irish Flora'', Oxford University Press. *Tutin, T. G. ''et al.'' (1964) ''

Flora Europaea The ''Flora Europaea'' is a 5-volume encyclopedia of plants, published between 1964 and 1993 by Cambridge University Press. The aim was to describe all the national Floras of Europe in a single, authoritative publication to help readers identify ...

'', Volume 1. Cambridge University Press. {{Wikispecies, Equisetum variegatum variegatum Flora of Saint Pierre and Miquelon Flora of England