Plants and Animals

Cystopteris laurentiana Laurentian fragile fern

Key Characteristics

Low arching fern (20-50 cm) of calcareous rocks; blades twice-divided, ovate to elongated, widest above the base; rachis and pinnae axis with occasional gland-tipped hairs.

Status and Rank

US Status: No Status/Not Listed
State Status: SC - Special Concern (rare or uncertain; not legally protected)
Global Rank: G3 - Vulnerable
State Rank: S1S2 - Rank is uncertain, ranging from critically imperiled to imperiled

Occurrences

CountyNumber of OccurrencesYear Last Observed
Chippewa 1 1993
Delta 3 2021
Dickinson 1 1985
Houghton 1 1992
Mackinac 1 2024
Marquette 1 1989

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 on limestone and dolomite boulders in the Niagaran Escarpment region of the eastern Upper Peninsula and on granite and limestone outcrops in the western Upper Peninsula.

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

Fragile fern, walking fern, maidenhair spleenwort, green spleenwort, polypody,and Braun's Christmas fern.

Management Recommendations

Requires moist to somewhat dry alkaline outcrops, and is likely impacted by excessive removal of overstory.

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 first week of June 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. 1993. Flora of North America, North of Mexico. Volume 2: Pteridophytes and Gymnosperms. Oxford University Press, New York. 475pp.
  • 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.
  • 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.
  • Lellinger, D.B. 1985. A field manual of ferns and fern allies of the United States and Canada.. Smithsonian Institute Press, Washington D.C. 389pp.
  • Mickel, J.T. 1979. How to know the ferns and fern allies. The Pictured Key Nature Series. William C. Brown Company, Dubuque. 229pp.