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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  Spirodela polyrrhiza (L.) Schleid. image
Photographer: John Kohout           

Elizabeth H. Zimmerman

Linda Ellis

Paul Skawinski
Family Lemnaceae
Spirodela polyrrhiza (L.) Schleid.
giant duckweed, greater duckweed
Spirodela: from Greek speira, "a cord," and delos, "evident," meaning "visible thread" and referring to the roots
polyrrhiza: polys for "many, frequent, much;" rhiza for "roots"
County distribution map- click for detailed distribution maps.
Detailed Distribution:
Town Range Maps
Google Dot Maps
Status: Native
Plant: floating perennial aquatic, clusters of several lobed leaves; stems none; 5-15 roots per leaf frond
Fruit:reproduces by budding; new leaves staying attached to clump
Leaf:irregular oval, green above, dark red below
Habitat: wet; ponds, lakes

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

Flora of North America (off site)
Lemna polyrrhiza L.
Spirodela polyrrhiza (L.) Schleid. var. masonii Daubs

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