Plants: robust and weak-stemmed; green to golden yellow; capitulum ± rounded in emergent forms, flat in submersed forms; lacking distinct terminal bud. Stems: green to brown; superficial cortex of 2 layers of thin-walled and enlarged cells. Stem: leaves triangular, 1–1.7 mm, apex acute to slightly obtuse; leaves usually appressed; margins entire; hyaline cells fibrillose and usually septate at base and sides. Branches: unranked, long and tapering, leaves greatly elongated at distal end. Branch: fascicles with 2 spreading and 2 pendent branches. Branch: stems green; cortex enlarged with conspicuous retort cells. Branch: leaves ovate-lanceolate to lanceolate, 3–5.5 mm; straight but sometimes slightly falcate-secund; weakly undulate and recurved when dry; margins entire; hyaline cells on convex surface with 0–1 pore per cell, on concave surface with round wall thinnings on the apices and angles; chlorophyllous cells narrowly triangular in transverse section and just enclosed on the concave surface. Sexual: condition dioicous. Spores: 26–29 µm; both surfaces distinctly papillose, appearing pusticulate to irregularly pusticulate; proximal laesura mostly less than 0.5 spore radius.
Forming wet often floating carpets in weakly minerotrophic mires. low to moderate elevations. St. Pierre and Miquelon (Miquelon), N.B., Nfld. and Labr. (Nfld.), N.S., Que., Ala., Conn., Del., Fla., Ga., La., Maine, Md., Mass., Miss., N.H., N.J., N.Y., N.C., Pa., R.I., S.C., Vt., Va.
Sporophytes are uncommon in Sphagnum torreyanum. See discussion under 24. S. atlanticum for taxonomic distinctions.