Rhizomes absent. Cauline stems slightly compressed, without spots, 4--75 cm; glands rarely present, black to gold, to 0.5 mm diam. Turions uncommon, lateral or terminal, 0.9--2.5 cm ´ 0.6--2 mm, soft; outer leaves 1--3 per side, base not corrugate, apex acute to apiculate; inner leaves rolled into hardened fusiform structure. Leaves submersed, ± spirally arranged, sessile, delicate; stipules persistent, inconspicuous, convolute, free from blade, greenish to brown or rarely white, not ligulate, 0.2--2.2 cm, delicate to fibrous, rarely shredding at tip, apex obtuse; blade pale green to olive-green, rarely somewhat reddish, linear, not arcuate, 1.3--8.2 cm ´ 0.3--2.3 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, acute to apiculate, rarely with bristle, lacunae rarely present, 0--2 rows each side of midrib; veins 1--3(--5). Inflorescences unbranched, emersed; peduncles not dimorphic, in axils of proximal, rarely distal leaves, recurved, clavate, 0.3--1.1(--3.7) cm; spikes not dimorphic, capitate to cylindric, 1.5--7 mm. Fruits pale green to olive-green or brown, obovate to nearly orbicular, turgid to concave, sessile, abaxially keeled, not laterally keeled, 1.4--2.7 ´ 1.1--2.2 mm, abaxial keel undulate, winglike; beak erect, 0.2--0.6 mm; sides without basal tubercles; embryo with 1 full spiral.
More
Stems to 7 dm, usually freely branched, slightly compressed, to 1 mm wide, usually without nodal glands; rhizome slender and elongate; lvs all submersed, linear, 1.5–8 × 0.5–2 mm, mostly acute or apiculate, 1–3(5)-veined, with 0–2 rows of lacunar cells flanking the midvein; stipulate sheaths axillary, free, greenish to brown, 0.5–2 cm, tubular, with connate margins, delicate to slightly fibrous; winter-buds uncommon, 1–2 cm, the inner lvs rolled into hard, fusiform structure; peduncles axillary, usually clavate, recurved, 5–15 mm, seldom longer; spikes mostly capitate,2–7 mm, with 1 or 2 whorls of fls; body of the fr 1.5–2.7 mm, with rounded to often concave sides andan undulate, wing-like dorsal keel, the beak 0.2–0.6 mm; 2n=28. Streams and ponds; N.S. and Que. toAlas., s. to W.I. and C. Amer. Ours is the widespread var. foliosus.
Home
