Synonymy

Eriophoretum angustifolii Lewis 1904, Lewis & Moss 1911, Watson 1932, Tansley 1939, all p.p.; Eriophorum angustifolium Gesellschaften Dierssen 1982.

Constant species

Eriophorum angustifolium.

Physiognomy

Eriophorum angustifolium is a frequent and locally abundant plant in both kinds of Sphagnum-dominated bog pool community in Britain but here it is a consistent dominant in swards where other vascular species and Sphagna play a relatively minor role. The shoot density of the cotton-grass is very variable and can change through time as clumps spread and die from behind; and the sward height may be very short or up to half a metre or more, though usually the shoots reach about 30 cm. No other vascular plants attain anything more than very occasional frequency, though a variety of Oxycocco-Sphagnetea species occur sporadically and sometimes with local prominence: there can be scattered small tussocks of Eriophorum vaginatum or Molinia caerulea or sparse individuals of Drosera rotundifolia, Erica tetralix or Empetrum nigrum ssp. nigrum. Bryophyte cover is likewise very variable and no species is constant but Drepanocladus fluitans is quite frequent and characteristic of this kind of vegetation, often growing submerged in flooded stands. There may also be some sparse shoots or small tufts of Sphagna, usually S. cuspidatum, but sometimes S. recurvum or S. papillosum, scattered Polytrichum commune, Odontoschisma sphagni or Gymnocolea inflata or, on drier patches, Campylopus brevipilus.

Habitat

The Eriophorum angustifolium community is typically found as small stands on barer exposures of acid raw peat soils in depressions, erosion channels or shallow peat cuttings on a wide range of mire types.

E. angustifolium is an important coloniser of bare peat, and, freed from the shading effect that its young shoots experience in thick Sphagnum carpets or among the vigorous growth of other vascular plants on mire flats and hummocks, is able to expand rapidly by vegetative growth of its rhizome system and become dominant on natural or artificial exposures (Phillips 1954).