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Kevin Doyle
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Smooth Black Sedge (Carex nigra)

Life history

Species overview

Smooth Black Sedge (Carex nigra), a Wisconsin Special Concern plant, is found mainly on the edge of dry meadows and wet sedge meadows and shrub-carr habitats. Blooming occurs May through September; fruiting occurs July through August. The optimal identification period for this species is early July through late August.

Synonyms: Carex acuta, C. goodenowii, C. nigra var. strictiformis, C. vulgaris var. striciformis

Identification

  • Distinguishing characteristics: Strongly rhizomatous; differs from the similar C. lenticularis by the rhizomatous habit, dark green leaves, black scales and perigynia, and short inflorescence bract
  • Flower characteristics: Staminate spikes 1 to 2, terminal; pistillate spikes 2 to 3, proximal.
  • Fruit characteristics: Perigynia ascending, pale brown with red-brown or black spots on the top half of the tip or occasionally black on the top half of the tip, 3 to 9 veins on each face.
  • Leaf characteristics: Basal sheaths red-brown; sheaths of proximal leaves glabrous.

Phenology

  • Blooming phenology: May through September
  • Fruiting phenology: July through August
  • Optimum time to identify: The optimal identification period for this species is early July through late August

Other

  • Growth form: Graminoid
  • Vegetative reproduction: Rhizomatous
  • Life cycle: Perennial
  • Section: Phacocystis
  • Comments: Associated Species: Alopecurus pratensis, Glyceria grandis, Carex stipata, Scirpus rubrotinctus.

State status

Status and Natural Heritage Inventory documented occurrences in Wisconsin

The table below provides information about the protected status - state and federal - and the rank (S and G Ranks) for Smooth Black Sedge (Carex nigra). See the Working List Key for more information about abbreviations. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Documented locations of Carex nigra in the Natural Heritage Inventory Database as of July 2015.


Summary Information
State StatusSC
Federal Status in Wisconsinnone
State RankS1
Global RankG5
Tracked by NHIY

Habitats and landscapes

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

General habitat information

  • Habitat description: Found mainly on the edge of dry meadows and wet sedge meadows and shrub-carr habitats.
  • Soils: Wet soils.

Natural communities

This table lists the natural communities that are associated with Smooth Black Sedge. Scores for natural community associations are: "significant" association (score=3), "moderate association" (score=2) or the species can be present but is only weakly associated with the community (score=1).

Ecological landscapes

This table lists the ecological landscape association scores for Smooth Black Sedge. The scores (3=High, 2=Moderate, 1=Low, 0=None) also correspond to the map.

Map of the Ecological Landscapes of Wisconsin.

Ecological landscape score
Central Lake Michigan Coastal 1
Superior Coastal Plain 3

Species guidance

The Endangered Resources Program has developed avoidance measures and management guidelines for plants on the Natural Heritage Working List. These are a work in progress, and we welcome your suggestions and feedback. Sources used in developing this information can be found here.

Avoidance measures

These are specific actions designed to avoid "take" (mortality) of this species.

  • Avoid known individual plant locations and conduct operations elsewhere when they are least likely to cause damage. Ideally, this would involve frozen, snow-covered ground. However, in areas of the state where frozen conditions are unreliable, very dry soils late in the growing season might be the best available alternative. Consult with a biologist, if needed.
  • Avoid broadcast spraying of herbicides; use care with spot spraying.

Management guidance

Management guidelines are additional considerations that may help maintain or enhance habitat for this species

  • Survey for and control invasive plants prior to conducting timber operations, as these can be spread by vehicles and often respond vigorously to increased light; see forestry BMPs for invasive species.
  • Prescribed burns and/or brushing may be beneficial (dependent on local site conditions).
  • Maintain and restore open habitat through selective clearing and brushing.

Photos


Smooth Black Sedge Photo.

Photo © Emmet Judziewicz.

Smooth Black Sedge Photo.

Photo © Emmet Judziewicz.

Smooth Black Sedge Photo.

Photo © Emmet Judziewicz.


Support for Wisconsin's rare plant information has been provided by the Division of Forestry, the Endangered Resources Fund and the Wisconsin Rare Plant Preservation Fund. To donate, visit the Natural Resources Foundation of Wisconsin [exit DNR].

Last revised: Wednesday, May 05, 2021
Southwest Savanna Southern Lake Michigan Coastal Western Coulees and Ridges Southeast Glacial Plains Central Sand Hills Central Lake Michigan Coastal Central Sand Plains Northern Lake Michigan Coastal Northern Lake Michigan Coastal Northeast Sands Western Prairie North Central Forest Northern Highlands Northwest Lowlands Northwest Sands Northwest Lowlands Superior Coastal Plains Forest Transition