Fernald's Sedge

Carex merritt-fernaldii Mackenzie

Carex merritt-fernaldii
Stuart Kooge

Monocotyledoneae (Monocots)
Cyperaceae (Sedge Family)
State Protection
Listed as Threatened by New York State: likely to become Endangered in the foreseeable future. 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
Imperiled or Vulnerable in New York - Very vulnerable, or vulnerable, to disappearing from New York, due to rarity or other factors; typically 6 to 80 populations or locations in New York, few individuals, restricted range, few remaining acres (or miles of stream), and/or recent and widespread declines. More information is needed to assign either S2 or S3.
Global Conservation Status Rank
Secure globally - Common in the world; widespread and abundant (but may be rare in some parts of its range).


Did you know?

The specific epithet merritt-fernaldii is named in honor of Merritt Fernald 1873-1950. Fernald discovered this species. He was one of the premier botanists in northeastern North America in the first half of the 20th century. He is the author of Gray's Manual of Botany, 8th edition, which has become the plant "bible" for this region.

State Ranking Justification

While we are only aware of eight known populations, this plant is certainly overlooked. There are nearly 20 historical locations, but those may or may not be useful in locating new sites. This is a disturbance-loving plant that may appear at a site for a short period of time and then return to the seed bank. As a Section Ovales sedge, many botanists either intentionally skip over identifying these or run into problems keying them out. With just a little experience, these can be easy to separate. More people who know how to identify this sedge are needed to search for it. With targetted surveys, additional populations are likely. These populations may be small though and the plant is subject to succession.

Short-term Trends

There are about a half dozen populations that have been seen in recent years. At a few of these populations the number of plants appears to have declined over a period of 10 or less years. Since this is a species of early successional habitat this should be expected. Other populations seen in recent years have only been seen once. These populations may have "reappeared" out of the seed bank as the result of a disturbance event. Since this is a species that fluctuates widely in above ground population size, it is difficult to assess short term trends. While one population may appear to be decreasing another population may be increasing. Overall, short term trends are not clear.

Long-term Trends

Currently only about a half dozen populations are known to be extant. There are approximately an additional 20 populations that have not been seen in recent years. It is unknown if these populations are still extant. Assessing the status of these populations might be difficult as C. merritt-fernaldii is a species that grows in early successional habitats and as the habitat matures, it remains dormant as seeds in the soil seed bank. Overall, long term trends are not clear.

Conservation and Management


There are currently no threats known to Carex merritt-fernaldii in New York.

Conservation Strategies and Management Practices

No management is currently needed.

Research Needs

Since historical populations may be difficult to find due to habitat maturing at these populations, surveys should be conducted in likely habitat in the general region of these historical populations.



Carex merritt-fernaldii occurs on rocky outcrops, ledges, sandy deltas, sandy roadsides, fields, and abandoned railroad grades. It often grows in sandy soils. Some data from New York indicates that this species grows in calcareous sites but this information is probably based on misidentified specimens as C. merritt-fernaldii is a species of acidic soils (New York Natural Heritage Program 2006). Dry sands, gravels, rocky places, meadows, roadsides, on acidic substrates (Mastrogiuseppe et al. 2002). Carex merritt-fernaldii is a species of early successional habitat and appears, presumably from the seed bank, after physical disturbances or fire, and then gradually dies out as the habitat undergoes succession. Typical habitat includes sandy or gravelly roadsides and ditch banks, sand barrens, gravel and sand pits, and rock ledges, always in relatively sterile acidic soils (Rothrock and Reznicek 2001). Dry gravelly or rocky banks, dryish meadows and borders of woods (Fernald 1970).

Associated Ecological Communities

  • Acidic talus slope woodland* (guide)
    An open to closed canopy woodland that occurs on talus slopes (slopes of boulders and rocks, often at the base of cliffs) composed of non-calcareous rocks such as granite, quartzite, or schist.
  • 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.
  • Gravel mine*
    An excavation in a gravel deposit from which gravel has been removed. Often these are dug into glacial deposits such as eskers or kames. Vegetation may be sparse if the mine is active; there may be substantial vegetative cover if the mine has been inactive for several years. Near-vertical slopes are used by bank swallows for nesting sites.
  • Pitch pine-oak-heath rocky summit* (guide)
    A community that occurs on warm, dry, rocky ridgetops and summits where the bedrock is non-calcareous (such as quartzite, sandstone, or schist), and the soils are more or less acidic. This community is broadly defined and includes examples that may lack pines and are dominated by scrub oak and/or heath shrubs apparently related to fire regime.
  • Roadcut cliff/slope*
    A sparsely vegetated cliff or steep slope, along a road, that was created by blasting or digging during road construction.
  • Rocky summit grassland* (guide)
    A grassland community that occurs on rocky summits and exposed rocky slopes of hills. Woody plants are sparse and may be scattered near the margin of the community. Small trees and shrubs may be present at low percent cover.
  • Sand beach
    A sparsely vegetated community that occurs on unstable sandy shores of large freshwater lakes, where the shore is formed and continually modified by wave action and wind erosion. Characteristic species that are usually present at very low percent cover include various grasses and other herbs.
  • Sand mine*
    An excavation in a sand deposit or sand dune from which sand has been removed. Vegetation is usually sparse.
  • Successional old field*
    A meadow dominated by forbs and grasses that occurs on sites that have been cleared and plowed (for farming or development), and then abandoned or only occasionally mowed.

* probable association but not confirmed.


New York State Distribution

Carex merritt-fernaldii occurs in northern, eastern, and southeastern New York including Long Island. It is also known from one disjunct population in western New York. The western New York population should be verified.

Global Distribution

Carex merritt-fernaldii is known from southwestern New Brunswick west to Maine, southern Quebec, southern Ontario, and southeastern Manitoba south to eastern Minnesota, Wisconsin, northern Michigan, New York, Connecticut and Massachusetts. It is also known from disjunct populations in northern Ohio and western New York. It is frequent in parts of New England and does not occur in large parts of southern Ohio, southern Michigan, and western New York because the acidic coarse soils that C. merritt-fernaldii prefers are lacking in these regions (Rothrock and Reznicek 2001, New York Natural Heritage Program 2006).

Identification Comments

General Description

Fernald's sedge is a tufted grass-like perennial. Leaves are 1.5-3.0 mm wide. As with other members of section Ovales, Fernald's sedge has two kinds of stems. Some stems have flower/fruit clusters (spikes) at their summits (reproductive stems) and some stems lack spikes (vegetative stems). The reproductive stems are 30-100 cm tall and have 4-10 stalkless spikes towards the top of the stems. The spikes have female flowers above and male flowers below. The female flowers develop into fruits (perigynia) which are 3.3-5.0 mm long, 2.3-3.5 mm wide, and papery thin (Mastrogiuseppe et al. 2002).

Identifying Characteristics

Carex merritt-fernaldii is densely cespitose and short rhizomatous or appears long rhizomatous in old clumps. The leaf sheaths are white hyaline adaxially and finely papillose. Leaf blades are 1.5-3.0 mm wide. Reproductive culms are 30-100 cm tall and the inflorescences are compact to open, or in large robust individuals they arch or nod. The spikes are (4-)6-8(-10) per culm, ovoid, and are rounded at the apices and bases. Pistillate scales are shorter than the perigynia. Perigynia are ascending, conspicuously 5-9 veined abaxially, veinless or faintly 1-5 veined adaxially, have broadly ovate to orbiculate bodies, are 2.3-3.5 mm wide, very papery thin, and have 1-2 veins in the yellowish wings (Mastrogiuseppe et al. 2002).

Best Life Stage for Proper Identification

This species is easiest to identify when it has just immature to mature perigynia which are not yet easily shedding. Caution should also be taken to use only inflorescences from the culms produced during the initial spring flush.

Similar Species

Carex bicknellii is similar to C. merritt-fernaldii and the two share coriaceous leaves, papillose leaf sheaths, and relatively few culms per tussock (Rothrock and Reznicek 2001). Carex bicknellii differs in having translucent, reddish-brown tinged mature perigynium wings, pistillate scales reddish brown, anthers longer [(2.4-)2.8-4.2 mm long], perigynia longer [(4.5-)5.1-6.7(-7.1) mm long] and wider [(2.4-)2.8-4.2 mm wide], and 4-8 adaxial veins over the achenes. In comparison, C. merritt-fernaldii has yellowish mature perigynium wings, pistillate scales yellowish brown, anthers shorter [1.3-2.6 mm long], perigynia shorter [3.3-5.0 mm long] and narrower [2.3-3.5 mm wide], and 1-5 faint adaxial veins over the achenes.

Carex brevior and C. molesta are perhaps somewhat similar. They have more coriaceous opaque perigynia with achenes not visible through the adaxial faces, perigynium wings at base of beak at most ciliate and somewhat symmetric, and smooth leaf sheaths. In comparison, C. merritt-fernaldii has more membranaceous translucent perigynia with achenes visible through the adaxial faces, perigynium wings at base of beak erose and asymmetric, and finely papillose leaf sheaths visible at high magnification (30-40X). In addition C. molesta has fewer spikes per culm [2-4(-5)] and shorter more compact inflorescences [1.3-3.0(-3.5) cm long]. In comparison, C. merritt-fernaldii has more spikes per culm [(4-)6-8(-10)] and longer sometimes more open inflorescences [1.5-5.0 cm long].

Best Time to See

Immature perigynia appear in mid-June, these mature to persist into late July, early August, and sometimes later. In the later part of this season the perigynia start to shed easily. In addition, occasional culms are produced throughout the growing season and these will produce flowers and fruits that mature later than the ones from the initial spring flush. These later culms will have more condensed inflorescences and are often not accounted for in floras and keys. Therefore, the best time to survey for Carex merritt-fernaldii is from mid-June to late July.

  • Fruiting

The time of year you would expect to find Fernald's Sedge fruiting in New York.

Fernald's Sedge Images


Fernald's Sedge
Carex merritt-fernaldii Mackenzie

  • Kingdom Plantae
    • Phylum Anthophyta
      • Class Monocotyledoneae (Monocots)
        • Order Cyperales
          • Family Cyperaceae (Sedge Family)

Additional Common Names

  • Sedge

Comments on the Classification

Carex merritt-fernaldii is in section Ovales. It is also in the informal Carex brevior group which in New York includes C. bicknellii, C. brevior, C. molesta, and C. festucacea. Carex merritt-fernaldii is closest to C. bicknellii (Rothrock and Reznicek 2001). Gleason and Cronquist (1991) lumped C. merritt-fernaldii under C. brevior but the two species are quite distinct and C. merritt-fernaldii is actually more closely related to C. bicknellii (Rothrock and Reznicek 2001).

Additional Resources

Best Identification Reference

Mastrogiuseppe, J., P.E. Rothrock, A.C. Dibble, and A.A. Reznicek. 2002. Carex Linnaeus sect. Ovales Kunth. Pages 332-378 in Flora of North America Editorial Committee (editors), Flora of North America, north of Mexico, Volume 23, Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford University Press, New York, New York, USA. 608pp + xxiv.

Other References

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

Rothrock, P.E. and A.A. Reznicek. 2001. The taxonomy of the Carex bicknellii group (Cyperaceae) and new species for central North America. Novon 11:205-228.

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


About This Guide

Information for this guide was last updated on: January 14, 2009

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Carex merritt-fernaldii. Available from: https://guides.nynhp.org/fernalds-sedge/. Accessed June 23, 2024.