Michaux’s sedge  (Carex michauxiana)

Michaux’s sedge has yet to be classified by the IUCN.

Michaux’s sedge (Carex michauxiana) is a perennial plant of bogs and other wet habitats in North America and Asia (2) (3) (4). Its stems, known as ‘culms’, are smooth, slender, fairly stiff, and triangular in cross-section (2) (4) (5). The yellowish-green leaves are arranged around the base of the stem (5) and measure up to about four millimetres in width (2). The uppermost leaves often exceed the stem in length (4).

As in other sedges (Cyperaceae species), the flowers of Michaux’s sedge are small, inconspicuous, and arranged in erect ‘spikes’ (5). These spikes are in turn arranged in clusters known as inflorescences, which in Michaux’s sedge measure up to 18 centimetres in length (2). In this species, the first few spikes on the inflorescence bear female flowers, while the outermost spike bears male flowers (2) (4).

Michaux’s sedge produces dry, one-seeded fruits, or ‘achenes’, which are oblong or egg-shaped (4) and up to three millimetres in length (2). As in other Carex species, each achene is enclosed within a sac-like structure known as a ‘perigynium’, which in Michaux’s sedge is yellowish-green and covered in veins. The perigynium of this species is quite narrow and tapers towards the tip, where it divides into two “teeth” (2) (4).

Michaux’s sedge occurs in central and eastern Canada and the north-central and north-eastern United States, as well as in parts of eastern Asia (2) (3) (4) (6).

Two subspecies of Michaux’s sedge are sometimes recognised, with Carex michauxiana michauxiana occurring in Canada and the United States, and Carex michauxiana asiatica occurring in the Russian Far East, Japan, China and Papua New Guinea (6). In North America, the range of this species extends west to Saskatchewan in Canada, and south to Minnesota, Wisconsin, Michigan, New York and Pennsylvania in the U.S. (2) (3) (4).

Michaux’s sedge typically inhabits wetland areas such as bogs, wet meadows and the shores of lakes and streams (2) (4).

Very little information is available on the biology of Michaux’s sedge. However, like other Carex species, it produces separate male and female flowers (5). Michaux’s sedge is reported to fruit in late spring and summer (2), from around June to September (4).

Like other sedges, Michaux’s sedge can produce new shoots from creeping underground stems known as rhizomes (5).

Michaux’s sedge is listed as ‘Endangered’ in Massachusetts and as ‘Threatened’ in Wisconsin (3). However, very little is known about the threats faced by this species, and its conservation status has yet to be assessed by the IUCN (7).

There are no specific conservation measures currently known to be in place for Michaux’s sedge.

Find out more about Michaux’s sedge:

• Flora of North America - Carex michauxiana:
  http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242357330