Equisetum telmateia
Giant horsetail
Image of Equisetum telmateia

Photo by William W. Brodovich 

Key Characteristics

Tall horsetail (up to 1 m) of moist meadows; fertile stems brown, appearing separately; sterile stems green with large hollow space and regular whorls of solid branches; branch ridges furrowed with rounded valleys.

Status and Rank

  • State Status: X
  • State Rank: SX
  • Global Rank: G5

Occurrences

County NameNumber of OccurrencesYear Last Observed
Keweenaw11895
Distribution map for Equisetum telmateia

Updated 1/31/2017. 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

Known from a single 1895 Michigan collection, where it was found in "damp alder thickets".

Natural Community Types

Methodology

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.

Feel free to send questions and comments to Brad Slaughter at slaugh14@msu.edu.

Associated Plants

Tag alder.

Management

The primary need at the present is status survey to determine if this species is extant within the state. If found, protection of hydrology would likely be important.

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 Mar 25, 2017]

References

Survey References

Technical References