OregonFlora species comparison

terete; to 200 cm; nodal glands absent.

terete to slightly compressed, 18– 150 cm; nodal glands present on at least some nodes; to 0.5 mm diameter, green; gold, brown, or rarely white.

submersed and floating or submersed only.

submersed, attached to stem nodes, not attached to stipules;

stipules connate, 3.1–9.2 mm, rarely fibrous;

tip obtuse;

blades linear, 14–65 × 0.5–1.9 mm;

base slightly tapering;

margins entire;

tip acute or rarely apiculate, rarely with a bristle; lacunae in 0–2 rows on each side of midrib;

veins 1–3.

elliptic or oblanceolate to obovate or oblonglinear, 40–70(100) × 10–25(40)mm; reddish green;

base gradually tapering to petiole;

tip obtuse or acute;

veins (7)9–13(15);

petioles 0–12 mm.

sessile, attached to stem nodes, not attached to stipules;

stipules (12)15–25(40)mm;

tip blunt;

blades oblong-linear to linear-lanceolate, 45–180(250) × 5–20 mm;

base rounded to cuneate;

margins entire;

tip obtuse or acute; lacunae in 0–6 rows on each side of midvein;

veins 7–9.

emersed;

spikes cylindric, 10–35 mm;

peduncles terminal or axillary; erect, 30– 100(160)mm.

submersed or emersed;

spikes cylindric, interrupted, 1.5–10.1 mm;

peduncles 1–3 per plant; axillary or terminal, filiform to cylindric; erect, rarely recurved, 5–66 mm.

pedicellate, obovoid; turgid; (2.5)3–3.5 × (1.7)2–2.4 mm, dorsally keeled, laterally keeled or not;

beaks dorsally curved, 0.5–0.9 mm.

sessile, obovoid;

sides centrally concave, 1.5–2.2 × 1.2– 1.6 mm, green to brown, not keeled;

beaks erect, displaced ventrally or rarely at middle of fruit tip, 0.1–0.6 mm.