Gymnocarpium robertianum (Hoffm.) Newman
Common Name: LIMESTONE OAK FERN
Coefficient of Conservatism: 10
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Nt Fern
Status: T
Gymnocarpium robertianum R. W. Smith

Calcareous cedar swamps, forests on thin soil over calcareous rock, calcareous ledges, pavement, and crevices, usually shaded and often with Thuja; very local.

The St. Clair County record dates from 1888.

Locations

Cheboygan County
Chippewa County
    Including Drummond Island
Delta County
Mackinac County
    Only on Bois Blanc, Mackinac, Round Islands
Marquette County
Montmorency County
Presque Isle County
St. Clair County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. July 22, 2018. https://michiganflora.net/species.aspx?id=530.