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Clasping-leaf Pondweed (Potamogeton perfoliatus)

Life history

Species overview

Clasping-leaf Pondweed (Potamogeton perfoliatus), a Wisconsin Special Concern plant, is found in lakes and streams with sandy or rocky substrate. Blooming occurs July to October; fruiting occurs July to October. The optimal identification period for this species is July to October.

Synonyms: Potamogeton bupleuroides, Potamogeton perfoliatus L. subsp. Bupleuroides, Potamogeton perfoliatus L. var. bupleuroides


  • Distinguishing characteristics: Distinguished from P. richardsonii by often perfoliate leaves (vs. clasping), more slender stems and rounded or ovate leaves (vs. lance-ovate and with a definite pointed tip).
  • Flower characteristics: Spike unbranched, cylindric, 1 to 7 cm.
  • Fruit characteristics: Greenish-brown, up to 3 mm and with a short beak, shallow pits and three dorsal keels or ridges.
  • Leaf characteristics: Alternate, 1 to 7 cm, round, often with a finely toothed tip and cordate bases wrapping entirely around stem (perfoliate); veins 7 to 15 with 3 to 5 prominent; stipules free, deciduous.


  • Blooming phenology: July to October
  • Fruiting phenology: July to October
  • Optimum time to identify: The optimal identification period for this species is July to October


  • Growth form: Aquatic forb-submergent
  • Vegetative reproduction:
  • Life cycle: Perennial
  • Comments: Associated Species: Not available for Wisconsin specimens.

State status

Status and Natural Heritage Inventory documented occurrences in Wisconsin

The table below provides information about the protected status - state and federal - and the rank (S and G Ranks) for Clasping-leaf Pondweed (Potamogeton perfoliatus). See the Working List Key for more information about abbreviations. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Documented locations of Potamogeton perfoliatus in the Natural Heritage Inventory Database as of July 2015.

Summary Information
State StatusSC
Federal Status in Wisconsinnone
State RankS1
Global RankG5
Tracked by NHIY

Habitats and landscapes

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

General habitat information

  • Habitat description: Found in lakes and streams with sandy or rocky substrate.
  • Soils: Sandy or rocky soils.

Natural communities

This table lists the natural communities that are associated with Clasping-leaf Pondweed. Scores for natural community associations are: "significant" association (score=3), "moderate association" (score=2) or the species can be present but is only weakly associated with the community (score=1).

Ecological landscapes

This table lists the ecological landscape association scores for Clasping-leaf Pondweed. The scores (3=High, 2=Moderate, 1=Low, 0=None) also correspond to the map.

Map of the Ecological Landscapes of Wisconsin.

Ecological landscape score
North Central Forest 2
Northern Highland 2
Northwest Sands 2

Species guidance

The Endangered Resources Program has developed avoidance measures and management guidelines for plants on the Natural Heritage Working List. These are a work in progress, and we welcome your suggestions and feedback. Sources used in developing this information can be found here.

Avoidance measures

These are specific actions designed to avoid "take" (mortality) of this species.

  • No avoidance measures have been developed for this species.

Management guidance

Management guidelines are additional considerations that may help maintain or enhance habitat for this species

  • This species is likely sensitive to water quality. Following BMPs around streams and buffering associated drainages will reduce eutrophication and prevent water quality degradation.


Clasping-leaf Pondweed Photo.

Photo ©  USDA-NRCS.

Support for Wisconsin's rare plant information has been provided by the Division of Forestry, the Endangered Resources Fund and the Wisconsin Rare Plant Preservation Fund. To donate, visit the Natural Resources Foundation of Wisconsin [exit DNR].

Last revised: Wednesday, May 05, 2021
Southwest Savanna Southern Lake Michigan Coastal Western Coulees and Ridges Southeast Glacial Plains Central Sand Hills Central Lake Michigan Coastal Central Sand Plains Northern Lake Michigan Coastal Northern Lake Michigan Coastal Northeast Sands Western Prairie North Central Forest Northern Highlands Northwest Lowlands Northwest Sands Northwest Lowlands Superior Coastal Plains Forest Transition