General: Perennial, aquatic herb from fine, tufted roots; stems up to 100 cm long, branched.
Leaves: All submersed, linear, thin, green, 5-10 cm long, up to 1 mm wide, with 1 to 3 veins, the tips sharp-pointed, the stipules 0.5-2 cm long, the blades arising close to the tips of the stipules.
Flowers: Inflorescence spikelike, the spikes 1.5-2.5 cm long, interrupted, with 2 to 5 whorls of flowers, the stalks thin.
Fruits: Achenes, almost globe-shaped, 3.5-4 mm long, 2.5-3 mm wide, widest above the middle, the beaks prominent, short, the keels absent, the surface without fine, ray-like grooves.
Lakes, ponds and estuaries in the lowland, steppe and montane zones; frequent in BC east of the Coast-Cascade Mountains, infrequent on the coast; cosmopolitan, N to AK, YT and NT, E to NF and S to ME, MA, PA, NC, FL, MS, LA, TX, NM, AZ and CA; Eurasia, Mexico, C and S Africa, C and S America, New Zealand, Australia.
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2013)
