OregonFlora species comparison

terete; to 200 cm; nodal glands absent.

slightly compressed, 4–75 cm; nodal glands common.

submersed and floating or submersed only.

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

stipules 2–22 mm, brown (rarely white), fibrous, shredding at tip;

veins persisting as fibers;

blades linear, 13–82 × 0.3–2.3 mm;

margins entire;

tip acute to apiculate; lacunae rarely present;

veins 1–3(5).

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.

emersed;

spikes interrupted, 1.5–7 mm;

peduncles axillary, recurved, 3–11(37) 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; round to obovoid, flattened, 1.4–2.7 × 1.1–2.2 mm, pale green, dorsally and laterally keeled;

beaks erect, 0.2–0.4 mm.