Littorella uniflora
American shore-grass
Image of Littorella uniflora

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
  • State Rank: S2S3
  • Global Rank: G5


County NameNumber of OccurrencesYear Last Observed
Distribution map for Littorella uniflora

Updated 5/15/2018. 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.


American shore-grass is found on the sandy-mucky shores of soft water lakes and submerged in depths of water up to 3 feet or more.

Natural Community Types


For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.

Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.

Associated Plants

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


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

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at [Accessed Aug 18, 2018]


Survey References

Technical References

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