Carex buxbaumii  Stuart Kooge

Carex buxbaumii
Stuart Kooge

Monocotyledoneae (Monocots)
Cyperaceae (Sedge Family)
State Protection
Federal Protection
Not Listed
State Conservation Status Rank
Global Conservation Status Rank


Did you know?

The specific epithet buxbaumii is for Johann Christian Buxbaum who lived from 1693-1730 (Fernald 1970).

State Ranking Justification

There are approximately ten known populations and as many as twenty additional historical locations. These populations are widely scattered throughout the entire state. This plant may be impacted by invasive wetland species. Only one population has over a thousand stems, with typical populations having a few hundred stems. Most of the Long Island historical locations are considered extirpated.

Short-term Trends

There are about 10 populations that have been seen in recent years. Exact trends at these populations is unknown. Most of these populations are not large but appear healthy. There is no reason to suspect that they are declining but there is no data to prove this assertion. Therefore, short term trends are unknown but are suspected of being stable.

Long-term Trends

At least four populations that occurred in the New York City area are believed extirpated. There are at least 20 additional populations that have not been seen in recent years. One of these populations was searched for without success but may still be extant. It is unknown if the other historical populations are still extant. Overall, long term trends are not clear but indicate at least some decline.

Conservation and Management


Currently there are no threats to populations of Carex buxbaumii but potential threats include development, invasive species, and flooding by beaver.

Conservation Strategies and Management Practices

Invasive species need to be monitored at one population and controlled if negatively impacting the habitat where the C. buxbaumii occurs. One site needs to be monitored for flooding by beavers and flooding needs to be prevented. At least one population needs to be protected from potential adjacent development.

Research Needs

All populations that have not been seen in recent years need to be surveyed to determine if they are still extant.



Carex buxbaumii occurs in a variety of wet habitats but prefers calcareous sites. It grows in rich fens, swamps, wet meadows, ice scoured river edges, lake shores, and vernal ponds. It is mostly found in relatively small patches (New York Natural Heritage Program 2006). Wet meadows, marshes, and fens (Murray 2002). Peat-bogs, marshes, wet meadows, and other wet places (Gleason and Cronquist 1991). Shores, meadows, marshes, and old bogs, often forming large stands; sometimes in marly bogs and marshes; in crevices and hollows of the rock shore of Lake Superior (Voss 1972). Wet shores, swamps, and bogs (Fernald 1970). Sunny swamps or wet meadows or springy places in calcareous regions (Mackenzie 1931-1935).

Associated Ecological Communities

  • Calcareous shoreline outcrop* (guide)
  • Cobble shore* (guide)
  • Inland calcareous lake shore* (guide)
  • Marl fen* (guide)
  • Red maple-tamarack peat swamp (guide)
  • Rich graminoid fen (guide)
  • Rich hemlock-hardwood peat swamp* (guide)
  • Rich shrub fen* (guide)
  • Rich sloping fen (guide)
  • Riverside ice meadow (guide)
  • Sedge meadow* (guide)
  • Vernal pool (guide)

Associated Species

  • Anthoxanthum nitens
  • Carex aquatilis (water sedge)
  • Carex flava (yellow sedge)
  • Carex interior (inland sedge)
  • Carex lasiocarpa
  • Carex prairea (prairie sedge)
  • Carex sartwellii (Sartwell's sedge)
  • Carex sterilis (dioecious sedge)
  • Carex tetanica (rigid sedge)
  • Cladium mariscoides (twig-rush)
  • Dasiphora floribunda
  • Eleocharis rostellata (walking spike-rush)
  • Eriophorum viridicarinatum (green-keeled cotton-grass)
  • Juncus balticus
  • Muhlenbergia glomerata (spike muhly)
  • Myrica pensylvanica
  • Oligoneruron ohioense
  • Parnassia glauca (common grass-of-Parnassus)
  • Phragmites australis ssp. americanus
  • Rhamnus alnifolia (alder-leaved buckthorn)
  • Toxicodendron vernix (poison-sumac)


New York State Distribution

Carex buxbaumii occurs widely scattered throughout most of New York. Populations from the New York City area appear to have been extirpated due to urbanization.

Global Distribution

Carex buxbaumii occurs in North America and Eurasia. In North America it is known from Alaska, Northwest Territories, and Greenland south to South Carolina, Ohio, Indiana, Illinois, Arkansas, Kansas, Colorado, Utah, Idaho, and Oregon (Murray 2002).

Best Places to See

  • Letchworth State Park (Livingston County)
  • Plotter Kill County Nature Preserve (Schenectady County)
  • Mendon Ponds County Park (Monroe County)

Identification Comments

General Description

Brown Bog Sedge is a loosely clumped grass-like perennial that grows in patches. The bases of the plants are purplish-red tinged. Leaves are strap-like, 2.0-3.5 mm wide, and light-green. Stems are 25-75 cm long and are terminated by one flower/fruit cluster (spike). This terminal spike has female flowers above and male flowers below. Also towards the apex of the stem are 2-4 cylindrical spikes composed entirely of female flowers. These spikes are on short, erect, secondary stems that attach to the main stem. The female flowers mature into fruit (perigynia) which are 2.5-4.0 mm long (Mackenzie 1931-1935, Murray 2002).

Identifying Characteristics

Carex buxbaumii is loosely cespitose and long rhizomatous. Basal leaf sheaths are purplish-red tinged and become fibrous as they degrade. Leaf blades are 2.0-3.5 mm wide and sometimes somewhat glaucous. Culms are 25-75 cm tall and bract blades are shorter than or longer than the inflorescences. The terminal spike is gynecandrous with the staminate portion creating a clavate base to the spike. There are 2-3(-4) lateral pistillate spikes 10-25 mm long, that are short pedunculate, erect, and are separate to somewhat approximate. The pistillate scales are light to often dark brown or purplish-brown and are acute to acuminate with a 0.5-3.0 mm long awn. Perigynia are gray-green or whitish, 2.5-4.0 mm long, densely papillose, and are without or with only a small beak (Mackenzie 1931-1935, Murray 2002).

Best Life Stage for Proper Identification

It is easiest to identify this species when it has just immature to mature perigynia but the perigynia are not easily shedding. Rhizomes are helpful in identification and should be collected.

Similar Species

Carex buxbaumii is a very distinctive sedge and should not easily be confused with other species in New York. Characters that help separate it from other species include the short pedunculate erect lateral spikes, gynecandrous terminal spike, ascending short or unbeaked perigynia, and elongated rhizomes.

Best Time to See

Carex buxbaumii starts to produce immature perigynia from early to late-June. These mature and persist until late July or August. Towards the end of this season the perigynia start to shed easily. Plants from warmer or more southern parts of New York will mature earlier and plants from cooler or more northern parts of New York will mature later. The best time to survey for this species is mid-June till mid to late July but location in the state should be factored into determining the best time to survey for C. buxbaumii.

  • Fruiting

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

Brown Bog Sedge Images


Brown Bog Sedge
Carex buxbaumii Wahlenb.

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

Additional Common Names

  • Buxbaum's sedge
  • Sedge


  • Carex polygama Schkuhr 1801 not Gmelin 1796

Comments on the Classification

Carex buxbaumii is in section Racemosae. Many authors had previously placed C. buxbaumii in section Atratae but Racemosae is an older name (Mackenzie 1931-1935, Murray 2002). The only other member of section Racemosae that occur in New York is C. atratriformis (Murray 2002).

Additional Resources

Best Identification Reference

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.

Other References

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

Mackenzie, K.K. 1931-1935. Cariceae. North American Flora 18: 1-478.

Murray, D.F. 2002. Carex Linnaeus sect. Racemosae G. Don. Pages 401-414 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, NY, USA. 608pp + xxiv.

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. 2019. 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.

Voss, E.G. 1972. Michigan flora: A guide to the identification and occurrence of the native and naturalized seed-plants of the state. Part I. Gymnosperms and monocots. Cranbrook Institute of Science and Univ. Michigan Herbarium. Ann Arbor. 488 pp.

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: May 21, 2006

Please cite this page as:
New York Natural Heritage Program. 2019. Online Conservation Guide for Carex buxbaumii. Available from: Accessed March 25, 2019.

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