Bradley's Spleenwort

Asplenium bradleyi D.C. Eat.

Asplenium bradleyi
Paul Redfearn

Class
Filicopsida (Ferns)
Family
Aspleniaceae (Spleenwort Family)
State Protection
Endangered
Listed as Endangered by New York State: in imminent danger of extirpation in New York. For animals, taking, importation, transportation, or possession is prohibited, except under license or permit. For plants, removal or damage without the consent of the landowner is prohibited.
Federal Protection
Not Listed
State Conservation Status Rank
SH
Historical (Possibly extirpated) in New York - Missing from New York; known only from historical records (more than 30 years ago), but still some possibility of rediscovery upon further searching.
Global Conservation Status Rank
G4
Apparently Secure globally - Uncommon in the world but not rare; usually widespread, but may be rare in some parts of its range; possibly some cause for long-term concern due to declines or other factors.

Summary

Did you know?

There have only been two historical locations of this plant in New York. One is from "a hill near Newburgh" in 1864 and the other is from the "Shawangunk Mountains" where it was observed in 1882 and 1895. More exploration of the Shawangunk cliff communities may result in its rediscovery. The plant is named for its discoverer Professor Frank H. Bradley, 1838-1879, naturalist and geologist from Indiana. The genus name Asplenium comes from a name (Asplenon) used by Dioscorides for a fern supposed to cure diseases of the spleen.

State Ranking Justification

Even though there is plenty of available habitat and numerous surveys have been conducted to find this fern, no populations are known today. There are two historical reports, one from Newburgh which is feared extirpated and one from the Shawangunk Mountains where potential habitat abounds. While this plant was last reported in New York in 1895, we still believe there is a high probability that it will be rediscovered. The most likely location for rediscovery is somewhere within the Shawangunk Mountains.

Short-term Trends

This plant was last reported in New York in the late 1800s. As such, a short-term trends assessment is not possible.

Long-term Trends

This plant has only been reported twice in New York. The first report was in the mid-1800s and the second report in the late 1800s. With only a few reports to start with and no reports in over one hundred years, a long-term trends assessment is not possible.

Conservation and Management

Threats

With no known populations, a threats assessment is difficult. Considering this plant's similarities to Asplenium montanum though, they probably share similar threats. The greatest threat to Asplenium montanum is destruction of its habitat, albeit from rock climbing or mining activities. As an unusual and rare plant, this particular fern is also threatened by collection. This collection could come from fern enthusiasts or unscrupulous botanists.

Conservation Strategies and Management Practices

The management needs will likely be similar to those for Asplenium montanum. With no known populations in New York, precise management needs are not known.

Research Needs

To assist with locating any population within New York, a habitat analysis from known sites closest to New York should be conducted. With this information, better focused surveys could take place in New York.

Habitat

Habitat

A fern historically known from rock faces within the Shawangunk Ridge, and nearby acid rock cliffs and rock faces (New York Natural Heritage Program 2004). In crevices of dry, shaded, acid rock outcrops (Rhoads and Block 2000). Noncalcareous cliffs and rocks or acid soil (Gleason and Cronquist 1991). A rock-loving fern often on high and dry bare cliffs, in very acid soils (Cobb 1984). Crevices of acidic rocks and cliffs (Fernald 1970).

Associated Ecological Communities

  • Cliff community (guide)
    A community that occurs on vertical exposures of resistant, non-calcareous bedrock (such as quartzite, sandstone, or schist) or consolidated material; these cliffs often include ledges and small areas of talus.

Range

New York State Distribution

As a very rare plant in New York, this fern is only known historically from a few collections within the Shawangunk Mountains. These historical populations are at the northern range limit for this species. The closest known populations are in southern Ohio and southern Pennsylvania.

Global Distribution

Bradley's spleenwort (Asplenium bradleyi) has a very spotty distribution over much of its range which includes the Appalachians and Ozark regions. The fern occurs from New Jersey and southern Pennsylvania, west to Illinois, and south to Oklahoma, Louisiana, and Georgia. Historically known from the Shawangunk Mountains of New York.

Identification Comments

General Description

This is a small, tightly packed fern that grows upright from the cracks in cliff faces and rocks. The leaves are 4-20 cm long and divided once into 6-14 pairs of triangular leaflets that have toothed edges. The lowest pair are the largest and the leaflets very gradually diminish in size toward the tip of the leaf. The lower half of the leaf stalk is black and shiny and the upper half is green.

Identifying Characteristics

The new stipes of this fern are blackish to lustrous for about half their length. The dark color present in the lower half of the rachis, with the rachis summit appearing green. The frond, with nearly parallel sides, is herbaceous or membranaceous but also evergreen. These fronds are oblong-lanceolate, 4-20 cm long, and pinnate. There are 6-14 or more short stalked pinnae on each side of the rachis, the lowest pinnae being the longest.

Best Life Stage for Proper Identification

To properly identify this plant, one needs mature fronds including leaves, rachis, and stipe. If only a picture is taken, some sort of scale reference should be provided within the picture to allow for verification.

Similar Species

Bradley's spleenwort (Asplenium bradleyi) very closely resembles mountain spleenwort (A. montanum) and may reflect a hybridization of A. montanum and A. platyneuron. Bradley's spleenwort will have a blade that is oblong with nearly parallel sides. The blade of mountain spleenwort is much more triangular in shape, tapering to the apex.

Best Time to See

While remnants of this plant are visible year-round, the fronds brown considerably after frost. The result is diminished or even missing plants until new fronds appear in spring. Some plants will remain green year-round though. Surveys for this plant should occur between May and October.

  • Vegetative
  • Fruiting

The time of year you would expect to find Bradley's Spleenwort vegetative and fruiting in New York.

Bradley's Spleenwort Images


Images of Similar Species

Taxonomy

Bradley's Spleenwort
Asplenium bradleyi D.C. Eat.

  • Kingdom Plantae
    • Phylum Filicinophyta
      • Class Filicopsida (Ferns)
        • Order Filicales
          • Family Aspleniaceae (Spleenwort Family)

Synonyms

  • Asplenium montanum x platyneuron
  • Asplenium x stotleri Wherry

Comments on the Classification

May reflect a hybridization of A. montanum and A. platyneuron. The sterile hybrid (2n=72) between these two species has also been called Asplenium x stotleri. If this plant does reflect a hybridization, the fertile alloploid (2n=144) is a self-reproducing species.

Additional Resources

Best Identification Reference

Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.

Other References

Cobb, Boughton. 1984. A field guide to ferns and their related families. 281 pp.. Houghton Mifflin Co., Boston, New York. The Peterson Field Guide Series.

Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.

Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.

Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp.

New York Natural Heritage Program. 2010. Biotics database. New York Natural Heritage Program. New York State Department of Environmental Conservation. Albany, NY.

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.

Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.

Rhoads, Ann F. and Timothy A. Block. 2000. The Plants of Pennsylvania, an Illustrated Manual. University of Pennsylvania Press, Philadelphia, PA.

Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://newyork.plantatlas.usf.edu/, Albany, New York

Links

About This Guide

Information for this guide was last updated on: May 31, 2006

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Asplenium bradleyi. Available from: https://guides.nynhp.org/bradleys-spleenwort/. Accessed March 28, 2024.