Plants moderate-sized, pale green, yellow-green to occassionally strongly reddish; growing in loose mats. Stems pale brown to green. Stem leaves very small, less than 0.8 mm, triangular with blunt rounded apex. Branches erect in distal portion of plants. Branch fascicles with 2 short spreading and 3 long tapering pendent branches. Branch leaves large, 2.8 mm or longer, sub-squarrose, ovate, involute to broad, truncate apex with more than 6 teeth; hyaline cells with to 6 non-ringed pores on convex surface with few or no pseudopores, 2--4 elliptic ringed pores on concave surface in corners or along commissures, internal commissural walls minutely papillose (best viewed in oblique sections), rarely smooth; chlorophyllous cells narrowly triangular in transverse section, more broadly exposed on convex surface, enclosed on concave surface. Sexual condition monoicous. Capsules with abundant pseudostomata on surface of capsule. Spores 31--43 µm; coarsely papillose on both proximal and distal surfaces, raised Y-mark sculpture on distal surface; proximal laesura moderately long, 0.4--0.7 spore radius.

Pioneer species among grasses on peaty sand, in pine barrens, burned-over savannas, in seeps in mountains inland; N.B., Nfld., N.S.; Ala., Fl., Ga., La., Maine, Md., N.J., N.C., S.C., Va.; Europe.

Capsules common, mature early- to mid-summer. Though they seldom if ever overlap ecologically, S. strictum and S. squarrosum both usually have squarrose branch leaves, but S. squarrosum has a lingulate fringed stem leaf that differs greatly from the triangular and entire margined stem leaf of S. strictum.