Montana Field Guide

Plants: Acrocarpous (Vitt 1988). Growing in uncrowded clumps of erect shoots, soft, pale to deep green. Stems 10-25 mm in height (FNA 2007), commonly branched; rhizoids growing low on the stem (Lawton 1971).

Leaves: Extremely twisted, curled and wavy when dry, 3-6 mm in length, lance-shaped with ovate tendencies, becoming suddenly subulate above, the subula nearly tubulose above; base enveloping the stem (FNA 2007), but not extending down it (Crum & Anderson et al. 1981); margins smooth or occasionally toothed distally (FNA 2007), erect (Crum & Anderson et al. 1981); costa usually extending to the apex (FNA 2007) or very shortly beyond it (Lawton 1971).

Leaf Cells: Lamina 1 cell-layer thick except margins may be of 2 layers; upper laminal cells smooth, nearly square or slightly lengthened, thick-walled; lower laminal cells somewhat long and quadrangular, smooth, thick-walled; alar cells not distinct; costa in X-section with guide cells, adaxial and abaxial stereid bands, the abaxial band larger (Lawton 1971), frequently a little coarse on the dorsal surface above (Crum & Anderson et al. 1981).

Fruit ripens the last part of spring into the first part of summer (FNA 2007).

Differs from the similar O. virens which has less strongly crisped leaves that taper steadily to the subula and do not envelop the stem (FNA 2007).

Often on decaying wood beside streams or inundated places, less frequently on soil, stones and evergreen tree bottoms (FNA 2007).

Autoicous, the perigonia situated just beneath the perichaetia. Seta upright, spiraled when dry, 8-21 mm in height. Capsule bowed, tilted to level, shrunken below the opening with a swelling at the base, 0.8-2 mm in length, somewhat straw-colored, grooved when dry; beak of the operculum slanted (Lawton 1971); peristome single, the 16 brilliant-red, 2-lobed teeth split to about midway (FNA 2007) with papillae above. Calyptra like a draping hood (FNA 2007).