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Maidenhair Spleenwort (Asplenium trichomanes)

Life history

Species overview

Maidenhair Spleenwort (Asplenium trichomanes), a Wisconsin Special Concern plant, is found on cool, shaded cliffs, mostly in hardwood forests; on basalt and related rocks (Penokee Range), sandstone (Wisconsin Dells), and dolomite (Door County). This species can be identified year-round.

Synonyms: None


  • Distinguishing characteristics: Pinnae nearly oval, not much longer than wide. Distinguished from A. trichomanes-ramosum by the rachis, which is dark reddish-brown throughout, and not becoming green toward the top.
  • Flower characteristics:
  • Fruit characteristics: Sori single, 1 mm long, elongate, and following the straight or slightly curved veins on the abaxial surface of the laminae; indusia long, thin, opaque, greenish, suberose to entire.
  • Leaf characteristics: Numerous uniform, linear, pinnate 5 to 25 cm long and 1.7 cm wide fronds with purple-brown rachis that can reach 6 cm in length; pinnae slightly lobed.


  • Blooming phenology:
  • Fruiting phenology: mid summer
  • Optimum time to identify: This species can be identified year-round


  • Growth form: Fern
  • Vegetative reproduction: Rhizomatous
  • Life cycle: Perennial
  • Comments: Associated Species: Acer saccharum, Tilia americana, Thuja occidentalis, Acer spicatum, Picea glauca, Tsuga canadensis, Cystopteris fragilis, Polystichum braunii, Polypodium vulgare.

State status

Status and Natural Heritage Inventory documented occurrences in Wisconsin

The table below provides information about the protected status - state and federal - and the rank (S and G Ranks) for Maidenhair Spleenwort (Asplenium trichomanes). See the Working List Key for more information about abbreviations. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Documented locations of Asplenium trichomanes in the Natural Heritage Inventory Database as of July 2015.

Summary Information
State StatusSC
Federal Status in Wisconsinnone
State RankS2S3
Global RankG5
Tracked by NHIY

Habitats and landscapes

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

General habitat information

  • Habitat description: Found on cool, shaded cliffs, mostly in hardwood forests; on basalt and related rocks (Penokee Range), sandstone (Wisconsin Dells), and dolomite (Door County).
  • Soils: Calcareous soils.

Natural communities

This table lists the natural communities that are associated with Maidenhair Spleenwort. Scores for natural community associations are: "significant" association (score=3), "moderate association" (score=2) or the species can be present but is only weakly associated with the community (score=1).

Ecological landscapes

This table lists the ecological landscape association scores for Maidenhair Spleenwort. The scores (3=High, 2=Moderate, 1=Low, 0=None) also correspond to the map.

Map of the Ecological Landscapes of Wisconsin.

Species guidance

The Endangered Resources Program has developed avoidance measures and management guidelines for plants on the Natural Heritage Working List. These are a work in progress, and we welcome your suggestions and feedback. Sources used in developing this information can be found here.

Avoidance measures

These are specific actions designed to avoid "take" (mortality) of this species.

  • Avoid broadcast spraying of herbicides; use care with spot spraying.
  • Avoid direct disturbance to sensitive microsites such as seeps, cliffs, and moss-covered boulders.
  • Avoid known individual plant locations and conduct operations elsewhere when they are least likely to cause damage. Ideally, this would involve frozen, snow-covered ground. However, in areas of the state where frozen conditions are unreliable, very dry soils late in the growing season might be the best available alternative. Consult with a biologist, if needed.

Management guidance

Management guidelines are additional considerations that may help maintain or enhance habitat for this species

  • Follow BMPs, especially around streams and use care near ravines, steep slopes, cliffs, rock outcrops, etc.
  • Maintain high forest canopy cover; this species requires shaded habitat conditions.
  • Buffer management around unique microhabitats such as ephemeral ponds, seeps, etc.


Maidenhair Spleenwort Photo.

Maidenhair spleenwort is a habitat specialist that occurs on bedrock features at several sites in the Northeast Sands.

Photo by Thomas Meyer, Wisconsin DNR.

Maidenhair Spleenwort Photo.

Photo by Ryan Clemo, Wisconsin DNR.

Maidenhair Spleenwort Photo.

Photo © Emmet Judziewicz.

Maidenhair Spleenwort Photo.

Photo © Emmet Judziewicz.

Maidenhair Spleenwort Photo.

The rachis of maidenhair spleenwort is reddish brown throughout whereas the rachis of green spleenwort (A. trichomanes-ramosum) is mostly green.

Photo © Janeen Ruby.

Support for Wisconsin's rare plant information has been provided by the Division of Forestry, the Endangered Resources Fund and the Wisconsin Rare Plant Preservation Fund. To donate, visit the Natural Resources Foundation of Wisconsin [exit DNR].

Last revised: Wednesday, May 05, 2021
Southwest Savanna Southern Lake Michigan Coastal Western Coulees and Ridges Southeast Glacial Plains Central Sand Hills Central Lake Michigan Coastal Central Sand Plains Northern Lake Michigan Coastal Northern Lake Michigan Coastal Northeast Sands Western Prairie North Central Forest Northern Highlands Northwest Lowlands Northwest Sands Northwest Lowlands Superior Coastal Plains Forest Transition