Midland Sedge

Carex mesochorea Mackenzie

Carex mesochorea
Stephen M. Young

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 in New York - Very vulnerable to disappearing from New York due to rarity or other factors; typically 6 to 20 populations or locations in New York, very few individuals, very restricted range, few remaining acres (or miles of stream), and/or steep declines.
Global Conservation Status Rank
Apparently or Demonstrably Secure globally - Uncommon to common 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. More information is needed to assign either G4 or G5.


Did you know?

Humans may be contributing to the increased abundance of this sedge since one of the habitats it seems to prefer is abandoned fire pits. The specific name means midland and refers to its range.

State Ranking Justification

There are currently eight known populations of this relatively new arrival to New York State. At this time, we consider the presence of the sedge as the natural range extension of a sedge native to the Midwest. If this plant continues to spread, we may find new populations elsewhere within the state. Few threats are reported. This sedge seems to withstand fire and mowing, so it is rather resilient.

Short-term Trends

Populations that have been surveyed more than once are stable. Based on past trends (see long-term trends), we should expect to find more populations in the future.

Long-term Trends

Some sources suspect that this sedge is not native at the northern and eastern limits of its range. This sedge was first collected in New York in 1924 and again in the 1960s. Today we know of at least eight populations. Whether this is a non-native plant (introduced into the state due to direct human actions) or just the result of a natural range extension is not known. Based on this trend though, we should expect to find more populations in the future.

Conservation and Management


A few populations may be threatened by invasive plants, especially black swallowwort. The majority of populations are not threatened.

Conservation Strategies and Management Practices

This is a disturbance-loving species. Disturbance needs to be maintained and exotic species eliminated.

Research Needs

There has been considerable debate on whether this taxon is best treated as a full species (Carex mesochorea) or as a variety (Carex cephalophora var. mesochorea). A full taxonomic study of these two taxa is warranted, along with a complete herbarium review to verify the identity of each specimen. Once this review is complete, a study on the habitat requirements and northeastern distribution will be more possible. According to Flora of North America, this sedge is probably not native at the northern and eastern limits of its range. Since New York is near both the eastern and northern range limits, its nativity should be further evaluated. This may simply be due to natural range extension.



A sedge of dry sandy soils of maritime grasslands, oak woods, mowed cemeteries, paths, and fields (New York Natural Heritage Program 2004). Dry grasslands, roadsides, railroads (Flora of North America 2002). Open woods and (often adventive) grasslands (Fernald 1970). Dry soil and open woods (Gleason and Cronquist 1991).

Associated Ecological Communities

  • Hempstead Plains grassland (guide)
    A tall grassland community that occurs on rolling outwash plains in west-central Long Island. This community occurs inland, beyond the influence of offshore winds and salt spray.
  • Maritime grassland (guide)
    A grassland community that occurs on rolling outwash plains of the glaciated portion of the Atlantic coastal plain, near the ocean and within the influence of offshore winds and salt spray.
  • Mowed lawn
    Residential, recreational, or commercial land, or unpaved airport runways in which the groundcover is dominated by clipped grasses and there is less than 30% cover of trees. Ornamental and/or native shrubs may be present, usually with less than 50% cover. The groundcover is maintained by mowing and broadleaf herbicide application.
  • Oak openings* (guide)
    A grass-savanna community that occurs on well-drained soils. In New York, these savannas originally occurred as openings within extensive oak-hickory forests. The best remnants occur on dolomite knobs.
  • 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.
  • Red cedar rocky summit* (guide)
    A community that occurs on warm, dry, rocky ridgetops and summits where the bedrock is calcareous (such as limestone or dolomite, but also marble, amphibolite, and calcsilicate rock), and the soils are more or less calcareous. The vegetation may be sparse or patchy, with numerous lichen covered rock outcrops.
  • 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.
  • 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.

Associated Species

  • Anthoxanthum odoratum (sweet vernal grass)
  • Carex m├╝hlenbergii var. enervis
  • Carex pensylvanica (Pennsylvania sedge)
  • Carya glabra (pignut hickory)
  • Danthonia compressa (northern oat grass)
  • Danthonia spicata (poverty grass)
  • Deschampsia flexuosa
  • Quercus alba (white oak)
  • Quercus montana (chestnut oak)
  • Schizachyrium scoparium
  • Sorghastrum nutans (Indian grass)
  • Tridens flavus
  • Vaccinium pallidum (hillside blueberry)


New York State Distribution

A sedge known from Long Island to the Hudson Highlands and central New York. This sedge may be more common than its state rank would indicate, but few people are searching for this sedge.

Global Distribution

A sedge ranging from southern Quebec and Ontario, south to Maryland, West Virginia, Tennessee, Arkansas, and Texas, west to Wisconsin and Nebraska. Also known from the mountains of South Carolina.

Identification Comments

General Description

This sedge has stiff stems up to 1 meter long that stick out more than twice as long as the dense clump of narrow leaves. The fruiting spikes are crowded at the top of the stem in a dense oval head 0.7-1.8 cm long. Each individual flower bract (perigynium) is 3-3.5 mm long and 2-2.5 mm broad and concealed from below by a scale with long narrow tips.

Identifying Characteristics

A sedge of dry upland habitats with stiff stems up to 1 meter long and more than twice as long as the leaves. The plants are densely cespitose with leaves 2-5 mm wide. The fruiting spikes are crowded in a dense ovoid head that is 0.7-1.8 cm long. The sheaths are thickened at the summit with ligules up to 3 mm long. The scales of the spike are long-awned and the pistillate scales have three distinct nerves near the center. The scale body is equal to or nearly equal to the perigynia, thus concealing it. The perigynia is 3-3.5 mm long and 2-2.5 mm broad.

Best Life Stage for Proper Identification

The entire plant, with mature achenes, is needed for proper identification.

Similar Species

Carex cephalophora is almost identical to this sedge, but the perigynia is slightly smaller (2-3 mm long and about 1.5 mm broad), the body of the pistillate scales are shorter than the perigynia (largely exposing them), and the pistillate scale has a green midnerve with two obscure lateral nerves.

Best Time to See

This sedge flowers in spring, with fruits appearing by late spring to early summer. The fruits begin to fall off the plant by late summer, often losing many of the perigynia during the collection process. Field surveys should be conducted from late June to early August.

  • Fruiting

The time of year you would expect to find Midland Sedge fruiting in New York.

Midland Sedge Images


Midland Sedge
Carex mesochorea Mackenzie

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

Additional Common Names

  • Sedge


  • Carex cephalophora var. mesochorea (Mack.) Gleason

Comments on the Classification

Due to the similar morphologic features and frequent identification confusion, some authors understandably treat this as a variety of Carex cephalophora. Additional taxonomic work is needed to determine the proper relationship of these taxa.

Additional Resources

Best Identification Reference

Flora of North America Editorial Committee. 2002. Flora of North America, North of Mexico. Volume 23. Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford University Press, New York. 608 pp.

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.

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.

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: September 8, 2004

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Carex mesochorea. Available from: https://guides.nynhp.org/midland-sedge/. Accessed July 19, 2024.