Michaux's Sedge (Carex michauxiana)

Life history

Species overview

Michaux's Sedge (Carex michauxiana), a Wisconsin Threatened plant, is found on bog and fen mats near Lake Superior. Blooming occurs late May through early June; fruiting occurs early June through late August. The optimal identification period for this species is late June through early August.

Synonyms: Carex abacta

Identification

• Distinguishing characteristics: Cespitose; bract sheaths concave at apex; perigynia widely spreading, lanceolate, long-tapering to the apex; pistillate scales narrowly ovate, lacking awns; leaves 1.5 to 3.5 mm wide; staminate spikelet solitary, more or less terminal, but sessile to short-peduncled, and barely if at all projecting over the pistillate spikelets.
• Flower characteristics: Pistillate spikes 1 to 4, roughly as long as thick; staminate spikelet solitary, more or less terminal, but sessile to short-peduncled, and barely if at all projecting over the pistillate spikelets.
• Fruit characteristics: Perigynia spreading or the proximal somewhat reflexed, yellowish green, veined, essentially uninflated, lanceolate, 4 to 6 times long as wide and not over 3 mm wide, gradually long-tapering to the apex.
• Leaf characteristics: Ligules 1.2 to 3 mm, wider than long; blades yellowish green, M-shaped to flat, widest leaves 1.5 to 3.5 mm wide, smooth abaxially, minutely papillose adaxially, especially distally.

Phenology

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

Other

• Growth form: Graminoid
• Vegetative reproduction: Rhizomatous
• Life cycle: Perennial
• Section: Rostrales
• Comments: Associated Species: Carex exilis, C. lasiocarpa, Cladium mariscoides, Rhynchospora alba, R. fusca, Picea mariana, Larix laricina, Arethusa bulbosa.

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 Michaux's Sedge (Carex michauxiana). 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 on bog and fen mats near Lake Superior.
• Soils: Wet soils.

Natural communities

This table lists the natural communities that are associated with Michaux's 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 Michaux's 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

• Minimize disturbance to hydrology, including soil disturbance from rutting.
• This species is likely sensitive to water quality. Following BMPs around streams and buffering associated drainages will reduce eutrophication and prevent water quality degradation.
• Avoid rapid and dramatic reductions in canopy cover or basal area in wet areas to reduce risk of swamping.

Other resources

Links to additional Michaux's 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