Dryopteris expansa (Presl) Fraser-Jenkins & Jermy
Coefficient of Conservatism: 9
Coefficient of Wetness: 0
Wetness Index: FAC
Physiognomy: Nt Fern

Dryopteris expansa N. Martineau

Northern hardwood or mixed conifer-hardwood forests, usually on slopes and in ravines.

The very long and broad lower pinnules near the rachis make the lowest pinnae of this plant quite asymmetric compared with either D. carthusiana or D. intermedia. An evidently very rare glandular form has been collected twice; it is morphologically typical of D. expansa so apparently not of hybrid origin.


Baraga County
Gogebic County
Keweenaw County
    Including Isle Royale
Mackinac County
Marquette County
Ontonagon County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. July 2, 2022. https://michiganflora.net/species.aspx?id=1183.