OregonFlora species comparison

flattened, 10–90 cm; nodal glands absent.

flattened; to 100 cm; nodal glands absent.

submersed and floating or submersed only.

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

stipules persistent to deliquescent; to 0.5 cm;

tip obtuse;

blades linear, 12–90 × 4–10 mm;

base obtuse to rounded, not to slightly clasping;

margins conspicuously serrate; wavy;

tip round to acute; lacunae in 2–5 rows on each side of midrib;

veins 3–5.

narrowly oblanceolate to elliptic, 20–80 × 4–20 mm;

base acute;

tip rounded or bluntly cuspidate;

veins 11–41;

petioles 20–125 mm.

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

stipules 10–30 mm;

tip obtuse;

blades linear, 50–220 × 1–10 mm;

margins entire;

tip blunt to acute; lacunae forming a prominent band along the midvein;

veins 3–13.

emersed;

spikes cylindric, 8–40 mm;

peduncles axillary; erect, 15–50(160)mm.

emersed; terminal or rarely axillary;

spikes cylindric, 10–15 mm;

peduncles erect to ascending, 25–40 mm.

sessile; round to obovoid, flattened, dorsally and laterally keeled, 2.5–4.5 × 2–3.6 mm; greenish brown;

beaks erect, 0.5 mm.

sessile, obovoid; turgid to slightly concave, 6 × 2.5 mm, yellow to red or reddish brown, not dorsally or laterally keeled;

beaks apically recurved, 2–3 mm.