Asplenium rhizophyllum

L.

Walking-fern Spleenwort

G5Secure Found in 43 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
LowThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.154703
Element CodePPASP02180
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumFilicinophyta
ClassFilicopsida
OrderFilicales
FamilyAspleniaceae
GenusAsplenium
Synonyms
Camptosorus rhizophyllus(L.) Link
Other Common Names
Doradille ambulante (FR) Walking Fern (EN) walking fern (EN)
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.
Taxonomic Comments
FNA (1993, vol. 2), Kartesz (1994), and Weakley and the Southeastern Flora Team (2023) accept Asplenium rhizophyllum. Asplenium rhizophyllum is one of the diploid progenitors of the reticulately evolved Appalachian Asplenium complex and is a parent species (with A. montanum) of the fertile allotetraploid species A. pinnatifidum (FNA 1993, vol. 2, Weakley and Southeastern Flora Team 2023).The generic placement of this taxon is in accordance with the Pteridophyte Phylogeny Group I (2016).
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2023-09-27
Change Date1984-02-09
Edition Date2023-09-27
Edition AuthorsGeoffrey Hall (1998), rev. C. Nordman (2023).
Threat ImpactLow
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Walking-fern Spleenwort (Asplenium rhizophyllum) occurs in eastern North America, from southern Québec and New Hampshire west to northern Michigan, Wisconsin, and southeastern Minnesota, and south to Alabama, Arkansas and eastern Oklahoma. It is estimated that there are more than 1800 occurrences rangewide, including on on various National Forests, and in National Parks and other National Park Service lands, State Forests, State Parks, State Wildlife Management Areas and other conservation lands in eastern North America. Threats include fragmentation and loss of habitat due to development or quarrying for limestone or dolomite, and loss of forest canopy, such as from large clearcuts without retention of trees where these ferns occur.
Range Extent Comments
Walking-fern Spleenwort (Asplenium rhizophyllum) also known, simply as Walking fern, occurs in eastern North America, from southern Québec and New Hampshire west to northern Michigan, Wisconsin, and southeastern Minnesota, and south to Alabama, Arkansas and eastern Oklahoma. Range extent was estimated to be 2.3 million square kilometers, using herbarium specimens and photo-based observations documented between 1992 and 2023 (Flora of North America Editorial Committee 1993, GBIF 2023, iNaturalist 2023, Weakley and Southeastern Flora Team 2023).
Occurrences Comments
By applying a 1 km separation distance to herbarium records and photo-based observations of Asplenium rhizophyllum documented between 1992 and 2023, it is estimated that there are more than 1800 occurrences rangewide (GBIF 2023, iNaturalist 2023).
Threat Impact Comments
Threats include fragmentation and loss of habitat due to development or quarrying for limestone or dolomite, and loss of forest canopy, such as from large clearcuts without retention of trees where these ferns occur.
Ecology & Habitat

Habitat

Asplenium rhizophyllum occurs on shaded, usually moss-covered boulders and ledges, usually on limestone or other basic rocks (such as dolostone, calcareous siltstone, or amphibolite) but occasionally on sandstone or other acidic rocks, and rarely on fallen tree trunks, at elevations from near sea level up to 1000 meters, or rarely up to or above 1500 meters (Flora of North America Editorial Committee 1993, Weakley and Southeastern Flora Team 2023).

Reproduction

"Proliferations arising from leaf tips result in the formation of clonal patches, often dense and extensive, on the mossy boulders and ledges where it typically grows" (Flora of North America Editorial Committee 1993).
Terrestrial Habitats
Forest - HardwoodForest - MixedBare rock/talus/screeCliff
Other Nations (2)
United StatesN5
ProvinceRankNative
ArkansasSNRYes
KentuckyS5Yes
North CarolinaS3Yes
KansasS3Yes
ConnecticutSNRYes
MaineSXYes
MassachusettsSNRYes
New YorkS4Yes
MarylandSNRYes
New JerseyS4Yes
PennsylvaniaS5Yes
DelawareSXYes
MississippiS1Yes
MichiganS2Yes
AlabamaSNRYes
IllinoisS4Yes
West VirginiaS5Yes
OhioSNRYes
Rhode IslandS1Yes
GeorgiaS5Yes
South CarolinaS2Yes
VirginiaS5Yes
WisconsinSNRYes
OklahomaS3Yes
IndianaS5Yes
MissouriSNRYes
TennesseeSNRYes
New HampshireS1Yes
District of ColumbiaSNRYes
VermontS4Yes
MinnesotaSNRYes
IowaS4Yes
CanadaN4
ProvinceRankNative
OntarioS4Yes
QuebecS3Yes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentSmall (1-10%)Serious or 31-70% pop. declineHigh (continuing)
1.1 - Housing & urban areasSmall (1-10%)Serious or 31-70% pop. declineHigh (continuing)
3 - Energy production & miningSmall (1-10%)Serious or 31-70% pop. declineHigh (continuing)
3.2 - Mining & quarryingSmall (1-10%)Serious or 31-70% pop. declineHigh (continuing)
5 - Biological resource useRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)
5.3 - Logging & wood harvestingRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)

Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (43)
Arkansas (9)
AreaForestAcres
Clifty CanyonOzark-St. Francis National Forest1,963
Devils CanyonOzark-St. Francis National Forest1,877
Dismal CreekOzark-St. Francis National Forest9,160
East ForkOzark-St. Francis National Forest13,037
Gee CreekOzark-St. Francis National Forest7,957
Hurricane CreekOzark-St. Francis National Forest2,279
Indian CreekOzark-St. Francis National Forest7,855
Pedestal RocksOzark-St. Francis National Forest21,957
Richland CreekOzark-St. Francis National Forest571
Georgia (3)
AreaForestAcres
Ben GapChattahoochee National Forest1,292
Big MountainChattahoochee National Forest1,974
Ellicott Rock AdditionChattahoochee National Forest690
Illinois (1)
AreaForestAcres
Clear SpringsShawnee National Forest11
Indiana (1)
AreaForestAcres
Mogan RidgeHoosier National Forest8,435
Kentucky (1)
AreaForestAcres
WolfpenDaniel Boone National Forest2,835
Missouri (2)
AreaForestAcres
Irish Rare II Study AreaMark Twain National Forest1,226
Swan Creek Rare II Study AreaMark Twain National Forest7,310
North Carolina (9)
AreaForestAcres
Bald MountainPisgah National Forest11,085
Barkers Creek (addition)Nantahala National Forest975
Cheoah BaldNantahala National Forest7,795
Harper CreekPisgah National Forest7,325
Jarrett CreekPisgah National Forest7,485
Laurel MountainPisgah National Forest5,683
Overflow CreekNantahala National Forest3,379
SnowbirdNantahala National Forest8,489
South Mills RiverPisgah National Forest8,588
Oklahoma (1)
AreaForestAcres
Beech CreekOuachita National Forest8,303
South Carolina (1)
AreaForestAcres
Ellicott Rock 2Sumter National Forest517
Tennessee (2)
AreaForestAcres
Bald MountainCherokee National Forest11,743
Beaver Dam CreekCherokee National Forest5,070
Vermont (1)
AreaForestAcres
Griffith Lake 09084Green Mountain and Finger Lakes National Forests1,833
Virginia (8)
AreaForestAcres
Beards MountainGeorge Washington National Forest7,505
Beaver Dam CreekJefferson National Forest1,135
Brush MountainJefferson National Forest6,002
Crawford MountainGeorge Washington National Forest9,892
JerkemtightGeorge Washington National Forest16,687
Little AlleghanyGeorge Washington National Forest10,215
Southern MassanuttenGeorge Washington National Forest11,985
The FriarsGeorge Washington National Forest2,035
West Virginia (4)
AreaForestAcres
Dry ForkMonongahela National Forest657
Glady ForkMonongahela National Forest3,239
Middle MountainMonongahela National Forest19,020
North Mountain HopevilleMonongahela National Forest6,525
References (7)
  1. Flora of North America Editorial Committee (FNA). 1993a. Flora of North America north of Mexico. Vol. 2. Pteridophytes and gymnosperms. Oxford Univ. Press, New York. xvi + 475 pp.
  2. Global Biodiversity Information Facility (GBIF). 2023. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2023).
  3. iNaturalist. 2023. Online. Available: https://www.inaturalist.org (accessed 2023).
  4. 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.
  5. NatureServe. 2023. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  6. Pteridophyte Phylogeny Group I. 2016. A Community-Derived Classification for Extant Lycophytes and Ferns. Journal of Systematics and Evolution 54(6): 563–603.
  7. Weakley, A.S., and Southeastern Flora Team. 2023. Flora of the southeastern United States. Edition of April 14, 2023. University of North Carolina Herbarium (NCU), North Carolina Botanical Garden, University of North Carolina, Chapel Hill. 2105 pp.