Phragmites

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Phragmites australis, the Common Reed (see Reed (plant) for other species also called 'reed'), is a large grass native to wetland sites throughout temperate and tropical regions of the world. It is generally regarded as the sole species of the genus Phragmites, though some botanists divide the genus into three or four species.

It commonly forms extensive stands, up to a square kilometre or more (known as reedbeds); where conditions are suitable, it can spread at up to 5 m or more per year by horizontal 'runner' stems, which put down roots at regular intervals. The erect stems grow to 2–6 m tall, with the taller plants growing in areas with hot summers and fertile growing conditions. The leaves are broad for a grass, 20–50 cm long and 2–3 cm broad. The flowers are produced in a dense, dark purple panicle 20–50 cm long.

The Common Reed is a very important plant for wildlife and conservation, particularly in Europe and Asia, where several species of birds are strongly tied to large Phragmites stands, notably:-

Bearded Tit Panurus biarmicus
Reed Warbler Acrocephalus scirpaceus
Great Bittern Botaurus stellaris

In North America, the species' status was misunderstood. It was commonly considered to be an exotic species, not native but introduced from Europe; however, there is clear evidence of the existence of Phragmites native in North America long before human colonisation of the continent. It is now known that the North American native forms of Phragmites are markedly less vigorous than European forms, and that the recent marked increase in Phragmites in North America is due to a vigorous, but otherwise almost indistinguishable European form of the species, best detectable by genetic analysis. This is causing serious problems for many other North American wetland plants, including the local form of the species.

Recent studies have characterised morphological variation among the introduced and native stands of Phragmites in North America. The Eurasian genotype can be distinguished from the North American genotype by its shorter ligules (up to 0.9 mm vs. over 1.0 mm), shorter glumes (under 3.2 mm vs. over 3.2 mm, although there is some overlap in this character), and culm characteristics. Recently, the North American genotype has been described as a distinct subspecies, Phragmites australis subsp. americanus Saltonstall, Peterson, and Soreng; the Eurasian genotype is referred to as Phragmites australis subsp. australis.

Rhizome of the plant is rich in N,N-DMT alkaloids (Wassel et al. 1985).

Synonyms include Arundo phragmites L. (the basionym), Phragmites altissimus, P. berlandieri, P. communis, P. dioicus, P. maximus, P. vulgaris.

In literature

The most famous reference to reeds in European literature is probably Frenchman Blaise Pascal's saying that Man is but a 'thinking reed' (roseau pensant). In La Fontaine's famous fable (Le chêne et le roseau), the reed tells the proud oak: "I bend, and break not" ("Je plie, et ne romps pas"), before the tree's fall.

External links

[Cryptic invasion by a non-native genotype of the common reed, Phragmites australis, into North America] (pdf file)

Image:Phragmites australis1.jpg|Reed stems in flower, in France Image:Riet Phragmites australis planten.jpg|Reed growth in early summer Image:Reed.jpg|Roadside reed left from previous year, in Hungary

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