Clustered Sedge Carex cumulata (Bailey) Fern.
Carex cumulata
Troy Weldy
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.
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.
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.
The specific name cumulata refers to the way the spikelets are piled up, like cumulus clouds, at the top of the stem. There are over 15 historical records for the species in New York and we expect to find more new populations as the search for this sedge continues.
The sedge is known from at least 15 populations where it is the dominant plant at several sites. There are several historical populations and lots of habitat that remains unchecked. As a plant that responds well to fire, populations may fluctuate widely depending on the current successional state of the immediate site. There are probably more populations present, particularly on the ridgetops of the Hudson Highlands, Shawangunk Mountains, and Taconic Ridge.
Populations that have been surveyed more than once are stable.
The number of populations seems to have declined over time but many historical records have not been checked. This sedge is easy to overlook and with more targeted surveys we may find that it is still doing well.
There are no current threats.
For the most part, this plant needs no active management. It does respond well to fire, so an occasional wildfire may prove beneficial.
There are no research needs at this time.
A sedge of open rocky habitats, particularly in damp areas on acidic bedrock or shallow soil. Also found in recently burned areas with shallow soils and exposed bedrock, powerline corridors, open oak or woodlands, heathlands, and various successional habitats (New York Natural Heritage Program 2004). Dry, rocky or sandy soil (Gleason and Cronquist 1991). Dry or moist acid soils (Fernald 1970).
Brushy cleared land*
A former forest, woodland, or shrubland that has been clearcut or cleared by brush-hog. The cut stumps of trees and shrubs are evident and usually common. There may be a lot of woody debris such as branches and slashings from trees that were logged. Vegetation is patchy, with scattered herbs, shrubs, and tree saplings. * probable association but not confirmed.
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. * probable association but not confirmed.
Mowed roadside/pathway*
A narrow strip of mowed vegetation along the side of a road, or a mowed pathway through taller vegetation (e.g., meadows, old fields, woodlands, forests), or along utility right-of-way corridors (e.g., power lines, telephone lines, gas pipelines). The vegetation in these mowed strips and paths may be dominated by grasses, sedges, and rushes; or it may be dominated by forbs, vines, and low shrubs that can tolerate infrequent mowing. * probable association but not confirmed.
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.
Pitch pine-oak-heath woodland* (guide)
A pine barrens community that occurs on well-drained, infertile, sandy soils. The structure of this community is intermediate between a shrub-savanna and a woodland. Pitch pine and white oak are the most abundant trees. * probable association but not confirmed.
Pitch pine-scrub oak barrens (guide)
A shrub-savanna community that occurs on well-drained, sandy soils that have developed on sand dunes, glacial till, and outwash plains.
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. * probable association but not confirmed.
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.
Shrub swamp (guide)
An inland wetland dominated by tall shrubs that occurs along the shore of a lake or river, in a wet depression or valley not associated with lakes, or as a transition zone between a marsh, fen, or bog and a swamp or upland community. Shrub swamps are very common and quite variable.
Aronia arbutifolia (red chokeberry)
Carya glabra (pignut hickory)
Danthonia compressa (northern oat grass)
Fraxinus americana (white ash)
Quercus ilicifolia (scrub oak, bear oak)
Quercus montana (chestnut oak)
Quercus rubra (northern red oak)
Schizachyrium scoparium
Spiraea tomentosa (steeplebush)
Vaccinium pallidum (hillside blueberry)
An Ovales sedge with scattered populations in the Champlain Valley, Hudson Valley, and a few remote populations westward. The majority of plants in New York are found in the Shawangunk Mountains, Hudson Highlands, and Taconic Mountains.
A sedge ranging from Prince Edward Island to Wisconsin, south to New Jersey and Illinois.
This is a sedge with many sturdy stems up to 80 cm tall. They stick out at angles above the clump of many narrow leaves. The green to brown conelike flower spikes are rounded at the bottom and always crowded toward the top of the stem. Each individual flower bract (perigynium) is 2-3.4 mm broad and without nerves on the inside face.
This sedge is characterized by coarse stout culms up to 80 cm tall. The leaf sheaths are loose and green-veined nearly to the summit or with a sharp Y-shaped hyaline area at the summit. The leaf blades are mostly 3-6 mm broad. The inflorescence is compact during the entire growing season with 3-30 stiffly erect and crowded spikes. These spikes are hut-shaped (squared to slightly rounded at the base, broadly tapering to a cone-like top), and green to brown in color. The perigynia are 2-3.4 mm broad and nerveless on the inner face. Once a person has been familarized with this sedge, the combination of habit and habitat make this one of the easier Ovales to identify.
While this sedge can be identified in flower, entire stems with mature fruit should be collected to allow for easy verification.
This sedge may resemble many of the sedges within the Ovales section, particularly if it is a late season Ovales. In late season, many of the Ovales have congested inflorescences. To distinguish this sedge from others within the Ovales, careful detail should be given to the inflorescences and perigynia. Within New York, the Ovales that are most often confused by Carex cumulata are Carex bicknellii, Carex brevior, Carex merritt-fernaldii, and Carex molesta. All of these have perigynia that are nearly ovate, with a clear membranaceous band near the top of the sheath.
This sedge begins to appear by mid-May with fruits forming by mid to late June. These fruits begin to separate from the plant by late summer. Surveys should be conducted late June to early September.
The time of year you would expect to find Clustered Sedge fruiting in New York.
Clustered Sedge Images
Clustered Sedge
Carex cumulata (Bailey) Fern.
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.
Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.
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.
Information for this guide was last updated on: January 14, 2009
New York Natural Heritage Program. 2021. Online Conservation Guide for Carex cumulata. Available from: https://guides.nynhp.org/clustered-sedge/. Accessed January 21, 2021.