Sporobolus heterolepis
Prairie dropseed
Image of Sporobolus heterolepis

Photo by Jodi B. Raab 

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Key Characteristics

Densely tufted grass of moist prairies and alvar; leaves very narrow and often inrolled, up to 50 cm tall; fruiting culms up to 1 m tall, bearing small spherical grains on an open, branching panicle.

Status and Rank

  • State Status: SC
  • State Rank: S3
  • Global Rank: G5


County NameNumber of OccurrencesYear Last Observed
Van Buren32005
Distribution map for Sporobolus heterolepis

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.


In Michigan, prairie dropseed is known from a variety of habitats, including prairie fens in the southern Lower Peninsula, in mesic sand prairies surrounded by pine barrens in the northern Lower Peninsula, and in alvar grasslands in the Upper Peninsula, where this species comprises an important portion of the thin turfs formed over limestone and dolomite bedrock.

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

Tamarack, grass-of-parnassus, shrubby cinquefoil, Virginia mountain mint, Ohio goldenrod, Riddell's goldenrod, Indian grass, hardstem bulrush, three-square, twig-rush, small white lady's slipper, bog valerian, little bluestem, big bluestem, colic root, wild indigo, common horsetail, path rush, hairy pinweed, pale spiked lobelia, meadowsweet, bulrush sedge, flattened spike-rush, ragwort, cat's foot, Canadian milk vetch, harebell, sedges, Indian paintbrush, field chickweed, bastard toad flax, hair grass, prairie smoke, ground juniper, bee-balm, and old field goldenrod.


This species requires protection of hydrology, groundwater source, and natural disturbance regime. It also benefits from management that includes prescribed fire and brush removal, which maintains open habitat and reduces competing woody vegetation. Control invasive species, especially glossy buckthorn. Where this species occurs in alvar habitat, it may be susceptible to damage from excessive recreational use and foot traffic.

General Survey Guidelines

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

Survey Methods

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at http://mnfi.anr.msu.edu/explorer [Accessed Sep 22, 2018]

More Information

See MNFI Species Abstract


Survey References

Technical References

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