Plants and Animals
Eleocharis equisetoides Horsetail spike rush
Key Characteristics
Large clone-forming aquatic emergent spike-rush (150 cm) of softwater lakes; culms hollow, yellowish-green and very thick (5-10 mm), resembling a horsetail (Equisetum) with superficial joints and cross-partitions.
Status and Rank
US Status: No Status/Not Listed
State Status: SC - Special Concern (rare or uncertain; not legally protected)
Global Rank: G4 - Apparently secure
State Rank: S3 - Vulnerable
Occurrences
| County | Number of Occurrences | Year Last Observed |
|---|---|---|
| Barry | 3 | 2012 |
| Cass | 2 | 1915 |
| Hillsdale | 1 | 1989 |
| Jackson | 4 | 2010 |
| Kalamazoo | 1 | 1936 |
| Livingston | 3 | 2011 |
| Montcalm | 1 | 1941 |
| Oakland | 1 | 2022 |
| St. Joseph | 1 | 1954 |
| Van Buren | 2 | 1915 |
| Washtenaw | 7 | 2023 |
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
Found in shallow water in emergent marshes, lakeshore edges and ponds, particularly where waters or substrates are slightly acidic.
Natural Community Types
- Emergent marsh
- Inland lake, littoral, benthic
- Submergent marsh
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-plantain, sedges, spike-rush, northern manna grass, cut grass, smartweed, arrowhead, bur-reed, cat tails, wild rice, water-milfoil, watercress, great duckweed, three square bulrush, water-lily, spatterdock, and pondweed.
Management Recommendations
Protect habitat; maintain wetland hydrology and natural cycle of fluctuations in emergent marsh. Agricultural run-off has negative impacts. Protect habitat from development.
Survey Methods
Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgement of the investigator.
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Meander search
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Survey Period: From first week of August to fourth week of October
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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
- 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.
- 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.
- Swink, F. and G. Wilhelm. 1994. Plants of the Chicago Region, 4th ed. Indiana Academy of Science, Indianapolis. 921pp.
- Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 488pp.