Appalachian Shoestring Fern

Vittaria appalachiana Farrar & Mickel

Vittaria appalachiana
Alan Cressler

Filicopsida (Ferns)
Pteridaceae (Maidenhair-fern Family)
State Protection
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
Critically Imperiled in New York - Especially vulnerable to disappearing from New York due to extreme rarity or other factors; typically 5 or fewer populations or locations in New York, very few individuals, very restricted range, very few remaining acres (or miles of stream), and/or very steep declines.
Global Conservation Status Rank
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.


Did you know?

Most familiar ferns are recognized by their sporophytes - the spore-producing phase of their life cycle. However, Appalachian Shoestring Fern is known only from its gametophytic, or gamete-producing phase. Though sexual reproduction (and the resulting sporophytes) is unknown in this species, local populations are maintained via gemmae, or vegetative buds which can grow into new individuals.

State Ranking Justification

There are only three existing populations of unknown quality and one historical location in New York.

Short-term Trends

At two of the four known sites in the state, the plants are known to have persisted after the initial visit; at one of the other sites they were not seen on subsequent visits, and at the last they are believed to be extirpated.

Long-term Trends

This plant was first discovered in New York in 1983, and therefore long-term population trends are unknown.

Conservation and Management


Canopy removal is a potential threat to this species at the forested sites.

Conservation Strategies and Management Practices

No management needs are apparent.

Research Needs

Additional survey work is needed to determine the size of the remaining populations.



In New York Appalachian Shoestring Fern has been found growing on shaded outcrops and rock houses of conglomerate rock, and at one location on the base of a Betula trunk in a large forested wetland (New York Natural Heritage Program 2009). Cool, moist, heavily shaded outcroppings of non-calcareous rock and occasionally on nearby tree bases (Farrar and Mickel 1991). In dark moist cavities and rock shelters in noncalcareous rocks; occasionally epiphytic on tree bases in narrow ravines (FNA 1993).

Associated Ecological Communities

  • Ice cave talus community* (guide)
    A community that occurs on rocks and soil at the base of slopes of loose rocks (often below cliffs; these are talus slopes) that emit cold air. The emission of cold air results from air circulation among the rocks of the talus slope where winter ice remains through the summer. The vegetation is distinctive because it includes species characteristic of climates much cooler than the climate of the area where the ice caves occur.
  • Red maple-tamarack peat swamp (guide)
    A swamp that occurs on organic soils (peat or muck) in poorly drained depressions. These swamps are often spring fed or enriched by seepage of mineral-rich groundwater resulting in a stable water table and continually saturated soil. The dominant trees are red maple and tamarack. These species usually form an open canopy (50 to 70% cover) with numerous small openings dominated by shrubs or sedges.
  • Talus cave community* (guide)
    The community that occurs in small crevices and caves with walls of boulders or cobbles, typically in a talus slope at the base of a cliff. This includes talus slopes that are cool enough to allow winter ice to remain within the talus through all or part of the summer; these are known as ice caves.

* probable association but not confirmed.

Associated Species

  • Betula alleghaniensis (yellow birch)


New York State Distribution

Appalachian Shoestring Fern is found in Cattaraugus and Chautauqua Counties in southwestern New York, and from a single site in the Catskills in Ulster County.

Global Distribution

Vittaria appalachiana occurs primarily in the Appalachian Mountains in unglaciated terrain, from southern New York south to northern Alabama, and as far west as Tenessee, Kentucky, Indiana, Ohio, and West Virginia (Farrar 1993).

Identification Comments

General Description

Vittaria appalachiana is a fern which normally produces only gametophytes, not the sporophytes most people recognize as ferns. They grow only on rocks or occasionally on the bases of tree trunks, and resemble liverworts or mosses more than they do other vascular plants. They often form dense mats as mosses do. Each gametophyte consists only of a simple green plant body about 0.6 to 2.4 cm long, and lacking roots, stems or leaves. They reproduce by means of gemmae, or buds, which grow from their tips. These gemmae are highly variable, often with the end cells swollen, and 2 to 12 body cells (FNA 1993, Cobb 1984).

Best Life Stage for Proper Identification

Gametophytes with gemmae, present through most of the growing season, are the only commonly seen life stage of this unusual fern.

Similar Species

Appalachian Shoestring Fern is the only Vittaria species known from the northeast. Once identified as a fern gametophyte, its higly variable gemmae (some with only 2 or 3 cells) are distinctive (FNA 1993, Cobb 1984).

Best Time to See

This species is best seen from May to early September.

  • Vegetative

The time of year you would expect to find Appalachian Shoestring Fern vegetative in New York.

Appalachian Shoestring Fern Images


Appalachian Shoestring Fern
Vittaria appalachiana Farrar & Mickel

  • Kingdom Plantae
    • Phylum Filicinophyta
      • Class Filicopsida (Ferns)
        • Order Filicales
          • Family Pteridaceae (Maidenhair-fern Family)

Additional Common Names

  • Appalachian Gametophytes
  • Appalachian Vittaria

Additional Resources


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.

Farrar, Donald R. and John T. Mickel. 1991. Vittaria appalachiana: A name for the "Appalachian gametophyte". American Fern Journal 81(3):69-75.

Farrar, Dr. Donald. 1993. Vittariaceae. In Flora of North America North of Mexico, Vol. 2. Flora of North America Editorial Committee (ed.). Oxford University Press, NY.

Flora of North America Editorial Committee. 1993. Flora of North America, North of Mexico. Volume 2. Pteridophytes and Gymnosperms. Oxford University Press, New York. 475 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.

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.

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 University of South Florida]. New York Flora Association, Albany, New York


About This Guide

Information for this guide was last updated on: March 9, 2009

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Vittaria appalachiana. Available from: Accessed June 21, 2024.