Potamogeton alpinus
Alpine pondweed
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Family: Potamogetonaceae · Type: Herb · Native
Potamogeton alpinus (Alpine pondweed) is a native California herb in the Potamogetonaceae family, recognized by reddish leaves and elevation distinctive.
Alpine pondweed is a California native perennial found in the Klamath Ranges, Sierra Nevada, Central Coast, and North Coast Ranges in ponds, lakes, and marshes at elevations of 1,300 to 2,350 meters. Flowering from July to September, this aquatic plant produces small, inconspicuous flowers in compact inflorescences less than 3 centimeters long. Growing with slender, rhizomatous stems up to 100 centimeters tall and few branches, it has a distinctive underwater growth pattern. Its underwater leaves are reddish, lanceolate to elliptic-oblong, 2 to 8 centimeters long and 1 to 2 centimeters wide, with 7 to 9 prominent veins and blunt tips. The fruits are small, approximately 2.5 millimeters long, with distinctive keeled edges.
Identification and appearance
Key characters: 15 sympatric species; reddish leaves and elevation distinctive
Habitat and range
Habitat: Uncommon. Ponds, lakes, marshes
Elevation: 1300-2350 m
Outside California: to Alaska, Greenland, Colorado, eastern Asia
Bloom period
Potamogeton alpinus blooms Jul-Sep.
How to tell it apart
vs Persicaria: Potamogeton flowers float on water; Persicaria has terrestrial pink/white flower spikes above solid ground.; vs Stuckenia: Potamogeton flowers emerge above water on stiff stalks; Stuckenia flowers stay underwater on flexible stalks.; vs Alisma: Potamogeton has inconspicuous spike flowers; Alisma has showy white three-petaled flowers in branched clusters.; vs Ranunculus: Potamogeton has tiny greenish spike flowers; Ranunculus has bright yellow buttercup flowers with visible petals.; vs Myriophyllum: Potamogeton has broad or ribbon-like leaves; Myriophyllum has feathery, finely divided leaves like a bottlebrush.
Frequently asked questions
Is Potamogeton alpinus native to California?
Yes. Potamogeton alpinus is native to California (recorded as native).
When does Potamogeton alpinus bloom?
Potamogeton alpinus blooms Jul-Sep.
What plant family does Potamogeton alpinus belong to?
Potamogeton alpinus is in the Potamogetonaceae family, genus Potamogeton.
What habitat does Potamogeton alpinus grow in?
Potamogeton alpinus grows in Uncommon. Ponds, lakes, marshes.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.