Plants: 0.8–5 cm. Stem: leaves loosely erect, usually slightly contorted or curved when dry, lanceolate to narrowly lanceolate, 3–4 mm; margins revolute nearly to apex, entire; apex acuminate to narrowly acute; basal laminal cells elongate, walls thick, nodose or wavy; distal cells 7–13 µm, 1-stratose, papillae 1–3 per cell, conic or 2-fid, large. : Specialized asexual reproduction absent. Sexual: condition gonioautoicous. Seta: 1–3 mm. Capsule: exserted to rarely emergent, cylindric to ovate-cylindric when mature, 1.5–2.4 mm, slightly 8-ribbed to mid capsule; stomata superficial; peristome double; prostome absent; exostome teeth 8, separate to base, recurved, acute, coarsely papillose; endostome segments 8, well developed, usually present when capsule is old and dry, thick, stout, of 2 rows of cells, narrower than exostome teeth, yellowish brown, coarsely papillose. Calyptra: conic-oblong, smooth, hairy, hairs finely papillose. Spores: 13–26 µm.
Coniferous and deciduous trees, rock. low to high elevations (10-2000 m). Greenland, Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, P.E.I., Que., Sask., Yukon, Alaska, Calif., Colo., Idaho, Mich., Minn., Mont., Nev., N.H., N.Y., Oreg., Utah, Wash., Wyo., Europe, n Asia, n Africa.
Orthotrichum speciosum is primarily western and Arctic in distribution; the plants are distinguished by their ribbed capsules, large size, and more slender leaf apices.