Plants and Animals

Eleocharis radicans Spike rush

Key Characteristics

Small mat-forming spike-rush (10 cm) of bogs; culms very soft and spongy, topped by small spikelets (2-3 mm) with pale brown scales; achenes very elongated, brown, with small pyramidal cap.

Status and Rank

US Status:
State Status: X - Presumed extirpated (legally 'threatened' if rediscovered)
Global Rank: G5 - Secure
State Rank: S1 - Critically imperiled

Occurrences

CountyNumber of OccurrencesYear Last Observed
Calhoun11905
Clinton12011
Eaton11905
Ingham12011
Livingston11930
Washtenaw11930

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.

Habitat

The Washtenaw locality where this spike-rush was collected is a sedge-sphagnum bog with a floating mat surrounding open water. There are no other Michigan data on habitat. Elsewhere this species occurs in wet sands and mucks, marshy pond and lakeshores, and often grows in floating mats. It was last documented in Michigan in 1930.

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

Sedges (Carex species, probably including C. lasiocarpa), sphagnum moss, and spike-rush (Eleocharis olivacea).

Management Recommendations

If found, it would likely require conservation of habitat and natural hydrological regime. Likely susceptible to invasive species, particularly purple loosestrife and glossy buckthorn.

Survey Methods

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

  • Meander search

    • Survey Period: From fourth week of July to fourth week of August

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

  • Flora of North America Editorial Committee. 2002. Flora of North America, North of Mexico. Volume 23: Magnoliaphyta: Commelinidae (in part): Cyperaceae. Oxford University Press, New York. 608pp.
  • 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.
  • Godfrey, R.K. and Wooten. 1981. Aquatic and Wetland Plants of Southeastern United States. Dicotyledons. University of Georgia Press, Athens. 712pp.
  • 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.
  • Rothrock, P.E. 2009 Sedges of Indiana and the Adjacent States, The Non-Carex Species. Indiana Academy of Science, Indianapolis, IN. 270 pp.
  • Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 488pp.