Asplenium bradleyi - D.C. Eat.
Bradley's Spleenwort
Other Common Names: Bradley's spleenwort
Taxonomic Status: Accepted
Related ITIS Name(s): Asplenium bradleyi D.C. Eat. (TSN 17338)
Unique Identifier: ELEMENT_GLOBAL.2.129065
Element Code: PPASP02050
Informal Taxonomy: Plants, Vascular - Ferns and relatives
 
Kingdom Phylum Class Order Family Genus
Plantae Filicinophyta Filicopsida Filicales Aspleniaceae Asplenium
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Concept Reference
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Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Asplenium bradleyi
Conservation Status
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NatureServe Status

Global Status: G4
Global Status Last Reviewed: 31May1993
Global Status Last Changed: 31May1993
Ranking Methodology Used: Ranked by calculator
Rounded Global Status: G4 - Apparently Secure
Reasons: Widespread species with localized distribution. Some parts of the range have greater threats than others, for example, some areas in the Appalachian Mountains are threatened by strip mining activities. This species is  more common than occurrence records indicate in some parts of the species range.
Nation: United States
National Status: N4

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alabama (S2), Arkansas (SNR), Georgia (S2), Illinois (S1), Indiana (S1), Kentucky (S3S4), Louisiana (SNR), Maryland (S1), Missouri (SU), New Jersey (S1), New York (SH), North Carolina (S2), Ohio (S1), Oklahoma (S1), Pennsylvania (S1), South Carolina (S1), Tennessee (S2S3), Virginia (S2), West Virginia (SH)

Other Statuses

NatureServe Global Conservation Status Factors

Range Extent Comments: Asplenium bradleyi has a very spotty distribution over much of its range which includes the Appalachians and Ozark regions (Werth pers. comm.). The species occurs from southern New York and New Jersey to Georgia and Alabama, west to Ohio, Missouri and Oklahoma (Gleason and Cronquist 1963).

Number of Occurrences: 81 - 300
Number of Occurrences Comments: "Occurring rarely to locally in the Appalachian region... but it is fairly frequent in the Ozark and Ouachita region... (FNA 1993)"

Overall Threat Impact Comments: One of the primary threats to A. bradleyi is the destruction of habitat through strip-mining activities (Werth pers. comm.). Within portions of the Appalachians, coal underlies the sandstone strata on which A. bradleyi grows. These activities are a significant threat in the Cumberland Plateau region of Kentucky and Tennessee.

Additional threats include the logging of upland forests above the cliff in such a way that slash is left against the cliff face (Ortt pers. comm.). Logging of adjacent forests may also be a threat due to changes in light levels and the consequent onset of desiccation brought about by such activities (Evans pers. comm.).

Rock climbers are another potential threat to existing populations (Ortt pers. comm., Schwegman pers. comm.). At one site in Ohio, climbers nearly destroyed a population. Fortunately, some plants survived in areas that were not accessed by the climbers (Ortt pers. comm.).

A population growing along a township road has been extirpated since the re-opening of the road roughly ten years ago (1980). It is unknown whether the population succumbed from physical damage by road work, change in air quality (dust/fumes) or some other subtle factor (Ortt pers. comm.).

Some plants have been killed by extreme drought conditions which deplete moisture within the rocks (Schwegman pers. comm.). Since A. bradleyi is a species typically found in habitats prone to severe drought, these events do not likely make a lasting impact on natural populations.

Short-term Trend: Decline of 10-30%
Short-term Trend Comments: Declining due to habitat destruction through strip-mining and other means.

Other NatureServe Conservation Status Information

Distribution
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Global Range: Asplenium bradleyi has a very spotty distribution over much of its range which includes the Appalachians and Ozark regions (Werth pers. comm.). The species occurs from southern New York and New Jersey to Georgia and Alabama, west to Ohio, Missouri and Oklahoma (Gleason and Cronquist 1963).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map

U.S. & Canada State/Province Distribution
United States AL, AR, GA, IL, IN, KY, LA, MD, MO, NC, NJ, NY, OH, OK, PA, SC, TN, VA, WV

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AL Clay (01027)*, DeKalb (01049)*, Etowah (01055)*, Jackson (01071)*, Lawrence (01079)*, Talladega (01121)*
GA Cobb (13067)*, Dade (13083)*, DeKalb (13089), Floyd (13115)*, Lincoln (13181)*, Rabun (13241)*, Stephens (13257)*, Upson (13293)*, Walker (13295)*
IL Gallatin (17059)*, Hardin (17069)*, Jackson (17077), Pope (17151), Randolph (17157), Saline (17165)*, Union (17181)*
IN Crawford (18025), Dubois (18037)
MD Baltimore County (24005), Harford (24025)
NC Burke (37023), Cleveland (37045)*, Gaston (37071), McDowell (37111), Orange (37135), Polk (37149), Rutherford (37161), Stokes (37169)
NJ Morris (34027), Warren (34041)*
NY Orange (36071)*, Ulster (36111)*
OH Athens (39009), Fairfield (39045), Pike (39131), Washington (39167)
OK Cherokee (40021)*, Latimer (40077), McCurtain (40089)*
PA Carbon (42025)*, Chester (42029), Lancaster (42071)
SC Chesterfield (45025)*, York (45091)*
VA Albemarle (51003)*, Buchanan (51027)*, Buckingham (51029), Campbell (51031)*, Dickenson (51051)*, Fluvanna (51065), Halifax (51083)*, Lunenburg (51111)*, Patrick (51141)*, Pulaski (51155)*, Rockingham (51165), Warren (51187)*
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
02 Rondout (02020007)+*, Hudson-Wappinger (02020008)+*, Hackensack-Passaic (02030103)+, Middle Delaware-Mongaup-Brodhead (02040104)+*, Middle Delaware-Musconetcong (02040105)+*, Lehigh (02040106)+*, Lower Susquehanna (02050306)+, Gunpowder-Patapsco (02060003)+, South Fork Shenandoah (02070005)+, Shenandoah (02070007)+*, Middle James-Buffalo (02080203)+, Rivanna (02080204)+*, Middle James-Willis (02080205)+*
03 Middle Roanoke (03010102)+*, Upper Dan (03010103)+, Meheriin (03010204)+*, Upper Neuse (03020201)+, Lower Pee Dee (03040201)+*, Upper Catawba (03050101)+, South Fork Catawba (03050102)+, Upper Broad (03050105)+, Tugaloo (03060102)+*, Upper Savannah (03060103)+*, Broad (03060104)+*, Little (03060105)+*, Upper Ocmulgee (03070103)+, Upper Chattahoochee (03130001)+*, Upper Flint (03130005)+*, Oostanaula (03150103)+*, Upper Coosa (03150105)+*, Middle Coosa (03150106)+*
05 Upper Ohio-Shade (05030202)+, Hocking (05030204)+, Upper New (05050001)+*, Lower Scioto (05060002)+, Upper Levisa (05070202)+*, Raccoon-Symmes (05090101)+, Patoka (05120209)+, Blue-Sinking (05140104)+, Lower Ohio-Bay (05140203)+, Saline (05140204)+*
06 Upper Little Tennessee (06010202)+*, Middle Tennessee-Chickamauga (06020001)+*, Guntersville Lake (06030001)+*
07 Upper Mississippi-Cape Girardeau (07140105)+, Big Muddy (07140106)+*
11 Lower Canadian (11090204)+, Illinois (11110103)+*, Poteau (11110105)+, Upper Little (11140107)+*
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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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.
Technical Description: Gleason and Cronquist (1963) described Asplenium bradleyi as follows:

"Rhizome ca. 1.5 mm thick, the numerous narrowly lanceolate scales blackish, 2-4.5 mm; fronds numerous, spreading, 7-25 cm, the stipe brown, to 9 cm; blade linear-oblong, to 20 x 4.5 cm, pinnate-pinnatifid to bipinnate, the rachis green for the distal third or half, brown below, bearing scattered slender scales; pinnae 8-15 pairs, alternate or the basal subopposite, short- stalked, deltoid to oblong-lanceolate, sometimes with only one free, superior basal segment (otherwise incised-serrate), or pinnate nearly throughout with 5 or more pairs of segments, these obtuse, sharply serrate."

Reproduction Comments: Asplenium bradleyi is a highly-variable allotetraploid species (Werth pers. comm.). Its putative parents are the wide-ranging A. platyneuron, and A. montanum, a species nearly restricted to the Appalachians (Werth et al. 1985). Hybridization has occurred several times in the history of this taxon, creating an impressive genotypic array (Werth pers. comm., Werth et al. 1985). For additional information pertaining to the allotetraploid origins of A. bradleyi, see Werth et al. (1985).
Terrestrial Habitat(s): Bare rock/talus/scree, Cliff, Sand/dune
Habitat Comments: Habitat includes the crevices of sandstone cliffs and ledges where other vegetation is typically lacking (Werth pers. comm.). The crevices in which the species occurs are typically large enough for A. bradleyi but too small for other larger fern species and flowering plants (Werth pers. comm.).

In Ohio, Asplenium bradleyi occurs in crevices on upper slopes of west to south facing sandstone outcrops (Ortt pers. comm.). Although this habitat type is plentiful within the state, occurrences of the species are few. Asplenium bradleyi grows on vertical or horizontal crevices but does not dwell on the ledges. Associates include Asplenium pinnatifidum, A. platyneuron and a few lichens.

In Missouri, A. bradleyi is scattered across 17 (mainly Ozarkian) counties, occurring on sandstone, granitic or chert bluffs in sheltered, dry, shaded crevices (Smith pers. comm.). Associates include some mosses adapted to dry sandstone. There is very little competition from other vascular plants.

Populations of A. bradleyi in Kentucky are known from dry, but mostly shaded sandstone cliffs (Evans pers. comm.). At times, A. montanum and A. pinnatifidum may occur nearby and may be considered associates.

In Illinois, A. bradleyi is found in crevices of sandstone cliff faces and cherty inclusions within limestone outcrops (Schwegman pers. comm.). Few other species grow in this harsh environment. Asplenium pinnatifidum is one of its few associates.

There are no known extant populations remaining in New York (Young pers. comm.). Two historic populations were known from the state, in the Shawangunk Mountains and the vicinity of Newburgh (NY NHP 1990).

Economic Attributes Not yet assessed
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Management Summary
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Stewardship Overview: Monitoring needs include a regular census of A. bradleyi populations, tracking numbers and locations of individuals. Research should be centered on the propagation requirements of the species, delineating the range of germination requirements. Research on the life history and ecology of A. bradleyi are needed to ascertain the habitat parameters and to be able to compare populations across its range. Maintenance of cliff face habitat is the primary habitat management need. Habitat protection from human disturbances (rock climbing) may be a need.
Restoration Potential: The recovery potential of A. bradleyi is not known at this time.
Preserve Selection & Design Considerations: Efforts aimed at protecting A. bradleyi sites should encompass sufficient buffer to protect the site from outside threats. Sufficient upslope buffer is needed to protect plants from upslope deforestation activities which may result in increased surface run-off. Protection efforts must protect the site from effects of strip-mining if the population is in an area which is underlain by coal.
Management Requirements: Protection of the cliff face habitat on which A. bradleyi lives is the primary management need. Habitat protection from human disturbances (rock climbing, upland deforestation, strip mining) is an additional need.

Management procedures should include the protection of the cliff face from all potentially-damaging effects. These habitats should be left off-limits to climbers. Maintenance of the upslope forests is a necessary management need.

Monitoring Requirements: A regular census of A. bradleyi should be instated at all protected population sites (Schwegman pers. comm.). Efforts designed to monitor recruitment should also be implemented.

Numbers of individuals at each site should be monitored on a regular basis (perhaps annually). In order to track recruitment, it may be worthwhile to create a comprehensive map of all existing plants. Mapping of extant plants may facilitate the gathering of information pertaining to population maintenance.


Management Programs: At present, no known management programs are in place for A. bradleyi.
Monitoring Programs: Marilyn Ortt of the Ohio Department of Natural Resources has been doing some monitoring of populations as a private project. The most intensely monitored sites are mapped with respect to position of plants on the outcrop and whether they occur on horizontal or vertical crevices. Fertile, infertile or dead plants are marked and tracked over time. At less intensely monitored sites, inventories of plant numbers and life stage are made. Three sites are visited annually.

Contact: Marilyn Ortt, Botanist, Ohio Natural Heritage Program, Botanical Inventory Subunit, 701 Colegate, Marietta, OH 45750. Telephone No. (614) 373-3372.

Management Research Programs: Dr. Charles Werth is conducting an on-going research project that is aimed at determining the range-wide genotypic variability in A. bradleyi using electrophoretic analysis of plant material.

Contact: Dr. Charles Werth, Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409. Telephone No. (806) 742-3222.

Paul Brown is currently conducting a survey for Asplenium bradleyi in New York. At present, there are no known populations remaining. Contact: Paul Brown, 15 Dresden Street, Jamaica Plain, MA 02130. Telephone No. (617) 524-5150.

Management Research Needs: Propagation requirements for A. bradleyi need to be studied. The range of germination requirements inherent in the species would provide information in determining if this is a limiting factor with regards to distribution and abundance (Ortt pers. comm.).

Research on the life history and ecology of A. bradleyi are also needed to ascertain the habitat parameters and to be able to compare populations across the range of the species (Ortt pers. comm.). Such information will help delineate species management needs, which in itself is a research need (Watson pers. comm.).

Additional inventory work is needed to determine the true range- wide status of the species (Young pers. comm.).

Population/Occurrence Delineation Not yet assessed
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Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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NatureServe Conservation Status Factors Edition Date: 25Jan2018
NatureServe Conservation Status Factors Author: Ostlie, W. R. (MRO), rev. Treher (2018)
Management Information Edition Date: 15Dec1990
Management Information Edition Author: WAYNE R. OSTLIE (1990), MRO
Element Ecology & Life History Edition Date: 15Dec1990
Element Ecology & Life History Author(s): WAYNE R. OSTLIE (1990), MRO

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

References
Help
  • 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.

  • Flora of North America Editorial Committee. 1993a. Flora of North America north of Mexico. Vol. 2. Pteridophytes and gymnosperms. Oxford Univ. Press, New York. xvi + 475 pp.

  • Gleason, H.A., and A. Cronquist. 1963. Manual of vascular plants of northeastern United States and adjacent Canada. D. Van Nostrand Company, New York, NY. 810 pp.

  • 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.

  • 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.

  • Hough, M. Y. 1983. New Jersey Wild Plants. Harmony Press, Harmony, New Jersey. 414 pp.

  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

  • 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.

  • Mohlenbrock, R.H. 1954. Some notes on the flora of southern Illinois. Rhodora 56:227-228.

  • Mohlenbrock, R.H. and J.H. Engh. 1964. Ferns and fern allies of Pine Hills Field Station and environs (Illinois). Amer. Fern J. 54(7):25-38.

  • New York Natural Heritage Program (NY NHP). 1990. Database records for Asplenium bradleyi. 4 pp.

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

  • Radford, A. E., H. E. Ahles, and C. R. Bell. 1968. Manual of the Vascular Flora of the Carolinas. University of North Carolina Press, Chapel Hill. 1183 pp.

  • 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.

  • SMITH, T. 1985. LETTER TO D.D. BOONE RE: ASPLENIUM BRADLEYII RECORD ON EDGAR WHERRY'S OLD QUAD MAPS.

  • Schwegman, J. 1990. Botany Program Manager, Illinois Department of Conservation. Personal communication: ESA questionnaire for Aspemium bradleyi. 4 pp.

  • Weber, W.R. 1970. A flora of Piney Creek Ravine. Trans. Ill. State Acad. Sci. 63:18-33.

  • 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://wwws.nyflora.org/, Albany, New York

  • Werth, C.R., S.I. Guttman, and W.H. Eshbaugh. 1985a. Recurring origins of allopolyploid species in Asplenium. Science 228: 731-733.

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