Asplenium trichomanes Linnaeus
maidenhair spleenwort
Family: Aspleniaceae

The blades of Asplenium trichomanes are once pinnate, the rachis is dark brown or purple and the sori are elongate. Blades are less than 25 cm long, less than 1.5 cm wide and are nearly uniform in width throughout the length except at the tip.

Two subspecies have been identified. Subspecies trichomanes is often found on acidic rocks, mostly in Iron County in the north and along the Wisconsin River in the south. Subspecies quadrivalens prefers calcareous rocks and in Wisconsin is found only in Door County.