Potamogeton robbinsii

Potamogeton robbinsii
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Alismatales
Family:	Potamogetonaceae
Genus:	Potamogeton
Species:	P. robbinsii
Binomial name
Potamogeton robbinsii Oakes

Potamogeton robbinsii, commonly known as Robbins' pondweed, is a North American perennial herb.

It is found in "deep to shallow, quiet, often muddy waters of lakes, ponds, and rivers."

This plant may form dense colonies that carpet the muddy substrates of riverbottoms and lakebeds. It rarely flowers, but when it does it is very easy to identify, as it is the only Potamogeton that has branching inflorescences.

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Wikipedia