Perennial, aquatic herb from strong rhizomes; stems mostly unbranched, often flexuous, nearly circular in cross-section, tapered, up to 200 cm long.
All submersed, linear-lanceolate, thin, flat, light green fading to white, 10-20 cm long, 2-4 cm wide, with 11 to 33 veins, clasping the stem, the tips rounded or hood-shaped, the stipules 3-10 cm long, fibrous or stringy; floating leaves absent.
Inflorescence spikelike, the spikes 3-5 cm long, with 6 to 12 whorls of flowers, the stalks inflated.
Achenes, widely egg-shaped or almost globe-shaped, 4.3-5.7 mm long, 3.2-4 mm wide, the beaks prominent, widely triangular, the keels wide.
Stem anatomical characters interlacunar bundles throughout the stem aerenchyma, subepidermal bundles absent, pseudohypodermis 1 to 3 cells thick, endodermis of U-cells.
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
Present over the Summer
Source: The USDA
||Value / Class
Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
of field plots
species was recorded in:
BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in
Source: Klinkenberg 2013
Synonyms and Alternate Names:
Potamogeton praelongus var. angustifolius Graebn.