Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Potamogeton robbinsii Oakes
- Family: Pondweed (Potamogetonaceae)
- Flowering: August-September
- Field Marks: The leaves of this submersed pondweed are numerous, linear to linear-lanceolate and minutely toothed, at least near the tip.
- Habitat: In deep water of ponds, lakes and streams.
- Habit: Submersed perennial with slender, creeping rhizomes.
- Stems: Rather stout, much branched, up to 2 feet long, smooth.
- Leaves: Alternate simple, all submersed, usually crowded, linear to linear-lanceolate, up to 4 inches long, up to 1/3 inch wide, pointed at the tip, united at the base with a stipule finely toothed, at least near the tips.
- Flowers: Few in stiff, interrupted spikes up to 1 inch long; stalks of spikes up to 3 inches long.
- Sepals: 4, reddish to greenish yellow, free from each other, 1/16-1/12 inch long.
- Petals: O.
- Stamens: 4.
- Pistils: 4, free from each other, smooth.
- Fruits: Achenes obovoid, up to 1/6 inch long, up to 1/8 inch wide, smooth, with the
persistent curved style at the tip.
- Notes: Most specimens of this species are rarely seen in flower and even more rarely in fruit. The plants provide cover for fish.
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