General:
Perennial, aquatic herb from fine, tufted roots; stems up to 100 cm long, sparsely branched.

Leaves:
All submersed, linear, the sides parallel, rigid, light to olive-green, 2.5-7 cm long, 1.2-3.5 mm wide, usually with 5 to 7 veins and narrow translucent bands (1 or 2 cells wide) along the midveins, blunt or rounded and slightly abruptly slender-tipped, the tips pointed, the stipules 0.5-2 cm long, coarsely fibrous, whitish, the tips shredding, the margins overlapping, basal glands present.

Flowers:
Inflorescence spikelike, the spikes 0.5-1.5 cm long, with 2 to 5 whorls of flowers, the stalks thin; winter buds fan-shaped, the bases hard, strongly ribbed.

Fruits:
Achenes, egg-shaped, 1.5-2.5 mm long, 1.2-2 mm wide, widest above the middle, the beaks short, the keels low and rounded.

Source:  The Illustrated Flora of British Columbia

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Illustration Source:  The Illustrated Flora of British Columbia