OregonFlora species comparison

terete; to 200 cm; nodal glands absent.

conspicuously flattened, 60–120 cm; nodal glands absent (rarely present), 0.3 mm diameter; gold.

submersed and floating or submersed only.

submersed, sessile; rigid, with blades attached at stem nodes, not attached to stipules;

stipules 15–35 mm, fibrous, shredding at tip;

tip obtuse to acuminate;

blades linear, 100–200 × 2–5 mm;

base rounded;

margins entire;

tip blunt, acuminate, or bristle-tipped; lacunae absent (but prominent midvein may sometimes appear lacuna-like);

veins 15–35.

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 cylindric, 15–30 mm;

peduncles usually terminal; erect to ascending, occasionally recurved, 20– 50 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.

quadrate-oblong or nearly orbicular; turgid, 4–5 × 3–3.5 mm, light green to olive-green, dorsally keeled;

keel wing-like;

beaks erect, 0.6–1 mm.