Synonymy

Reed-swamp Pallis 1911 p.p.; Phalaris arundinacea consocies Pearsall 1918; Phalaris arundinacea fen Tansley 1939; Phalaris arundinacea society and Phalaris-Filipendula sociation Spence 1964; Sociatie van Phalaris arundinacea Westhoff & den Held 1969; Tall grass washlands Ratcliffe 1977 p.p.; Phalaris nodum Daniels 1978; Angelico-Phragmitetum typicum sensu Ratcliffe & Hattey 1982 p.p.

Constant species

Phalaris arundinacea.

Physiognomy

The Phalaridetum arundinaceae comprises vegetation in which Phalaris arundinacea is dominant, forming an often dense canopy, usually 1-1.5 m tall. The vegetation is almost always species-poor and, although certain species attain prominence in some sub-communities, no associate is frequent throughout.

Sub-communities

Phalaris arundinacea sub-community. Here are included very species-poor stands overwhelmingly dominated by P. arundinacea. Some are pure; others have scattered associates as a very sparse understorey, sometimes small herbs or helophytes of water margins, in other cases, tall herbs and sprawlers of fens or salt-marsh plants.

Epilobium hirsutum-Urtica dioica sub-community. P. arundinacea generally remains dominant here but the canopy is more varied with mixtures of Epilobium hirsutum and Urtica dioica and, more rarely, Glyceria maxima. There is sometimes a little Galium aparine and very occasionally some Eurhynchium praelongum.

Elymus repens-Holcus lanatus sub-community. An often shorter but usually still closed canopy of P. arundinacea here has beneath it a grassy understorey with one or more of Elymus repens, Holcus lanatus, Poa trivialis and Deschampsia cespitosa. There are sometimes scattered plants of Ranunculus repens and Cirsium arvense but other species are rare.

Habitat

The Phalaridetum is typical of the margins of fluctuating, circumneutral and mesotrophic to eutrophic waters, both standing and running. Although it can be found on organic soils, it is more characteristic of mineral substrates, from fine clays to coarse gravels. It is common in open-water transitions around ponds and lakes of all sizes and also occurs around reservoirs, flooded clay and gravel pits, in some flood-plain and basin mires and, rarely, on salt-marshes. It is widespread, too, along periodically flooded dykes and by rivers, even swift and spatey hill streams, and may occur patchily on river shoals. The vegetation may be grazed by stock or wildfowl.