Robert W. Freckmann Herbarium


Because of technology changes and personnel changes at UWSP and the Wisconsin State Herbarium, the database of plant species housed at this site was merged with the database from the OLD WisFlora website to create a new Flora of Wisconsin website at Currently we are encouraging all Wisplant viewers to begin using the Flora of Wisconsin website as soon as possible. Wisplants will remain operational through July 13th. After that date, all traffic to Wisplants will be redirected to the Flora of Wisconsin website.

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  Potamogeton zosteriformis Fernald image
Photographer: Paul Skawinski           

Botanical Illustration

Andrew Hipp

Paul Skawinski

Paul Skawinski

Paul Skawinski

Robert W. Freckmann
Family Potamogetonaceae
Potamogeton zosteriformis Fernald
flat-stem pondweed, flat-stemmed pondweed
Potamogeton: from Greek potamos, "a river," and geiton, "a neighbor," because of the habitat
zosteriformis: like Zostera
County distribution map- click for detailed distribution maps.
Detailed Distribution:
Town Range Maps
Google Dot Maps
Status: Native
Plant: perennial, submersed aquatic; stems flattened, angled, freely branching; slight rhizomes
Flower: green-brown, small; inflorescence cylindrical spike, spike above the water
Fruit:oval, dry seed with a sharp, narrow dorsal ridge
Leaf:alternate, entire, with prominent midvein; stiff, linear, many fine parallel veins, none floating; firm stipules free in leaf axil;
Habitat: water from shallow to >12' deep; in soft sediment soil

More Information Natural Communities Herbarium Specimens
All Potamogeton list Google- Images or Text

Flora of North America (off site)
Potamogeton compressus auct. non L.
Potamogeton zosterifolius auct. non Schumach.
Potamogeton zosterifolius Schumach. subsp. zosteriformis (Fernald) Hultén
Potamogeton zosterifolius Schumach. var. americanus A.Benn.

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