General:
Perennial, aquatic herb from strong rhizomes; stems up to 200 cm long, unbranched.

Leaves:
Submersed leaves reduced to narrow, firm, dark green cylindrical stalks without blades, growing from the main stem, 10-20 cm long, the stipules 4-9 cm long, fibrous; floating leaves egg-shaped, 3-10 cm long, 2.5-6 cm wide, the larger ones with (18) 20 to 35 veins, leathery, long-stalked, the tips rounded, notched at the bases.

Flowers:
Inflorescence spikelike, the spikes with 6 to10 whorls of flowers, the stalks thick.

Fruits:
Achenes, broadly egg-shaped, 3.5-5 mm long, 2.5-3.5 mm wide, the beaks cylindrical, the keels obscure, developed in the upper half of achenes.

Notes:
Stem anatomical characters Interlacunar bundles present throughout the stem aerenchyma in several circles, subepidermal bundles present, pseudohypodermis 1-cell thick, endodermis of U-cells.

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

Flower Colour:
Green

Blooming Period:
Mid Summer

Fruit/Seed characteristics:
Colour: Brown
Present from Summer to Fall

Source:  The USDA