Photo by Michael R. Penskar 

Key Characteristics

Small tufted aquatic of marsh shorelines; stems all submerged, often forming mats from creeping stolons; leaves grass-like, cylindrical; flowers urn-shaped, white, with male and female on separate plants, the male flowers with conspicuously protruding stamens.

Status and Rank

• State Status: SC - Special Concern (rare or uncertain; not legally protected)
• State Rank: S2S3 - Rank is uncertain, ranging from imperiled to vulnerable
• Global Rank: G5 - Secure

Occurrences

County Name	Number of Occurrences	Year Last Observed
Alger	1	1988
Baraga	1	1966
Charlevoix	1	1998
Chippewa	2	1976
Delta	1	1994
Gogebic	1	1987
Iron	1	1987
Keweenaw	3	1982
Luce	4	1978
Ontonagon	1	1981
Schoolcraft	3	1996

Updated 05/08/2013. Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.

Natural Community Types

• Submergent marsh
• Inland lake, littoral, benthic
• Emergent marsh
• Intermittent wetland

Associated Plants

Water-milfoil, pipewort, horned bladderwort, flat-leaved bladderwort, water lobelia, and brown-fruited rush.

Management

Avoid or minimize herbicide use and maintain hydrological regime.

General Survey Guidelines

Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgment of the investigator.

Survey Methods

• Meander search

  Survey Period: From fourth week of June to fourth week of August

Page Citation

References

Survey References

• Elzinga, C.L., D.W. Salzer, and J.W. Willoughby. 1998. Measuring and Monitoring Plant Populations. The Nature Conservancy and Bureau of Land Management, Denver. BLM Technical Reference 1730-1. 477pp.

• Goff, G.F., G.A. Dawson, and J.J. Rochow. 1982. Site examination for Threatened and Endangered plant species. Environmental Management 6(4): 307-316

• Nelson, J.R. 1984. Rare Plant Field Survey Guidelines. In: J.P. Smith and R. York. Inventory of rare and endangered vascular plants of California. 3rd Ed. California Native Plant Society, Berkeley. 174pp.

• Nelson, J.R. 1986. Rare Plant Surveys: Techniques For Impact Assessment. Natural Areas Journal 5(3):18-30.

• Nelson, J.R. 1987. Rare Plant Surveys: Techniques for Impact Assessment. In: Conservation and management of rare and endangered plants. Ed. T.S. Elias. California Native Plant Society, Sacramento. 8pp.

Technical References

• Coffin, B. and L. Pfannmuller, eds. 1988. Minnesota's Endangered Flora and Fauna. University of Minnesota Press, Minneapolis. 473pp.

• Crow, G.E. and C.B. Hellquist. 2000. Aquatic and Wetland Plants of Northeastern North America. Volume 1. Pteridophytes, Gymnosperms, and Angiosperms: Dicotyledons. University of Wisconsin Press, Madison. 480pp.

• Gleason, H. A., and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. Second edition. The New York Botanical Garden, Bronx. 910pp.

• Gray, A. 1950. Gray's Manual of Botany; eighth ed. Van Nostrand Reinghold, New York. 1632pp.

• Holmgren, N.H. 1998. Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the vascular plants of Northeastern United States and adjacent Canada. New York Botanical Garden, Bronx. 937pp.

• Radford, A. E., H. E. Ahles, and C. R. Bell. 1968. Manual of the vascular flora of the Carolinas. University of North Carolina Press, Chapel Hill. 1183pp.

• Scoggan, H.J. 1978. The Flora of Canada. National Museum of Natural Science Publications Botany 4: 1711pp.

• Voss, E.G. 1996. Michigan Flora. Part III. Dicots (Pyrolaceae-Compositae). Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 622pp.

For assistance with this site, email mnfi@msu.edu

MSU Extension programs and materials are open to all without regard to race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, marital status or family status.