Misc. Bot. 13. 1804
Phenology: Flowering early summer–fall.
Habitat: Ponds, lakes, and slow-moving streams
Elevation: 400–2500 m
Greenland, Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon, Alaska, Calif., Colo., Idaho, Maine, Mass., Mich., Minn., Mont., Nev., N.H., N.J., N.Y., Oreg., Pa., S.Dak., Utah, Vt., Wash., Wis., Wyo., Europe, Asia Eurasia.
Plants of Potamogeton alpinus often are red whenever taken from the water, a feature that makes this species quite distinctive.
Two varieties, Potamogeton alpinus var. tenuifolius and var. subellipticus, have been recognized in North America, based mainly on submersed leaf shape. Plants bearing both leaf types have been observed in the same population; hence the varieties are not recognized.
Four hybrids, Potamogeton alpinus × P. nodosus (= P. ×subobtusus Hagström), P. alpinus × P. gramineus (= P. xnericius Hagström), P. alpinus × P. praelongus (= P. ×griffithii A. Bennett), and P. alpinus × P. perfoliatus (= P. ×prussicus Hagström), have been described.