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.

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.

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.

Other resources

Links to additional Smooth Black Sedge information

Other links related to vascular plants (all exit the DNR website)

• Wisconsin Flora
• NatureServe Explorer
• Atlas of Wisconsin Prairie and Savanna Flora - Wisconsin State Herbarium
• USDA - NRCS Plants Database
• USGS Midwestern Wetland Flora - field office guide to plant species
• eFloras
• Cofrin Center for Biodiversity Herbarium
• Intermountain Herbarium Grasses of North America
• Orchids of Wisconsin

Photos

Click to view a larger version. Please considering donating a photo to the Natural Heritage Conservation Program for educational uses. Photo use