Stems to 18 cm tall. Leaves appressed when dry, distinctly squarrose when moist, 6.1–10.2 mm long; lamina 0.5–0.8 mm wide, abaxial cells with distinctly incrassate outer walls; margin serrate with large sharp unicellular teeth, tightly upcurved, unistratose, 4–8 cells wide; sheathing base gradually widened; costa excurrent, with apical abaxial teeth; lamellae 34–52, on adaxial surface of blade, 5–10 cells high, ±straight to slightly crenate by upper margin, with apical cells retuse in cross-section and with an incrassate outer wall.
Urn 3.1–6.2 mm long, 1.6–3.5 mm wide. Spores 6–11 µm diameter.
Polytrichum commune usually has rather distant leaves with glossy sheathing parts covering the stem. However, this is true only of specimens growing in moist habitats. The typical, retuse, apical cells of the adaxial lamellae are a reliable and readily seen diagnostic character that is present in all specimens.
n = 7, cited in H.P. Ramsay, J. Hattori Bot. Lab. 82: 220 (1997).
Almost a cosmopolitan species with a distribution that includes New Zealand, the Pacific islands, Africa and South America. In Australia it occurs in Queensland, New South Wales, the Australian Capital Territory, Victoria and Tasmania.
Polytrichum commune is a plant of diverse open habitats; it is commonly found on peat.
Polytrichum commune Hedw., Sp. Musc. Frond. 88 (1801). Type: Europe; n.v.
Taxonomic synonyms
Polytrichum perigoniale Michx., Fl. Bor.-Amer. 2: 293 (1803); Polytrichum commune Hedw. var. perigoniale (Michx.) Hampe, Linnaea 13: 44 (1839). Type: Carolina, U.S.A.; holo: n.v.
Polytrichum brachypelma Müll.Hal., Hedwigia 36: 346 (1897). Type: "New South Wales, Sydney: Domina Kaysser in Hb. Geheeb 1872; Blue Mountains: Whitelegge 1884 in Hb. Melbourne sub Polytricho communi"; syn: Sydney, N.S.W., D.Kayser; n.v.; syn: Blue Mountains, N.S.W., 1884, T.Whitelegge; H-BR.
Polytrichum cataractarum Müll.Hal., Hedwigia 36: 347 (1897). Type: "New South Wales, Mossvale, Fitzroy falls: Whitelegge Nov. 1884. Hb. Melbourne 1885 misit"; iso: Fitzroy Falls, N.S.W., Nov. 1884, T.Whitelegge, NSW.
Qld: S of Bald Rock, I.G. Stone 13435 (MEL).
N.S.W.: Sams Creek, H. Streimann 49176 (CANB, H).
A.C.T.: Bimberi Range, P. Darbyshire 80 (MEL).
Vic.: Gorae West, A.C. Beauglehole 1462 (MEL).
Tas.: Mount Wellington, A.V. Ratkowsky H363 (HO).
Two varieties (var. commune and var. perigoniale) have been distinguished in Australia, but their status is still in dispute, and they are not recognised here.
H.A. Crum & L.E. Anderson, Mosses of Eastern North America 2: 1282, fig. 637 (1981); D.G. Long, Bioscience 17: 38, fig. 12 (1985); J. Beever, K.W. Allison & J. Child, Mosses of New Zealand, 2nd edn 27, fig. 12b (1992).
J. Hyvönen (2012), Australian Mosses Online 48. Polytrichaceae. Australian Biological Resources Study, Canberra. Version 20 June 2012.
First published as: J. Hyvönen (2006), Polytrichaceae: Polytrichum, Fl. Australia 51: 140–143. Australian Biological Resources Study, Canberra & CSIRO Publishing, Melbourne.
Author - J. Hyvönen
Editor(s) - P.M. McCarthy (2012); A.E. Orchard (June 2019)
Acknowledgements -
Contributors -
Cite this profile as: J. Hyvönen (2024) Polytrichum commune. In: Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water, Canberra. https://profiles.ala.org.au/opus/boa/profile/Polytrichum%20commune [Date Accessed: 29 July 2025]