Carex spp.
(Sedges)

Subclass: Commelinidae
Order: Cyperales
Family: Cyperaceae
Family Description: Sedge

Key Characteristics:
Grass-like, triangular stems, fused leaf sheaths.
leaves
flowers
fruit
  • Leaves are arranged in three ranks, they thus are a120 degrees apart.
  • The blades can be flat or filiform with sheaths that are fused around the stem.
  • Flowers are arranged in spikes which are usually subtended by a sheathless or sheathed leaf-like bract.
  • Apetalous flowers are unisexual and are subtended by a single, open bract.
  • Staminate flowers have three stamens.
  • Pistillate flowers also are surrounded by a perigynium which is a fused (closed) bract which is diagnostic in identifying a species.
  • Its parts are referred to as the body, beak and teeth.
  • Veins (called nerves) are diagnostic by number, and whether adaxial or abaxial.
  • Small diagnostic characteristics include length of beak, teeth or body, shape of body, nerves or lack there of, location of nerves and their number on either abaxial or adaxial side, winged margins or not and the number of styles and the overall shape of the style contained within the perigynium and where it is jointed.

General Description:
Carex plants are known to be difficult to identify and many studies just refer to them as sedges or “Carex spp.” They are grass-like plants, but unlike most grasses, sedges have triangular stems, fused leaf sheaths, and solid, pith-filled stems. Plants may be rhizomatous or clustered. The plants usually are monoecious with one or more staminate spike inflorescence and one or more pistillate spike inflorescence or the inflorescences may be composed of both staminate and pistillate flowers; if the male infloresence is terminal or the male flowers in any spike are terminal, the term covering this is that the plant is “androgynous.” If the pistillate inflorescence is terminal or the pistillate flowers are terminal in a spike with the staminate flowers at the bottom of the spike, the condition is referred to as “gynaecandrous.” Very seldom are plants dioecious. Spikes are subtended by a bract which can be large and leaf-like to small and inconspicuous or absent; spikes can be sessile or pedunculate and compactly or loosely arranged. flowers have no sepals and no petals; each flower is subtended by a small, scarious bract referred to as a “scale.” Staminate flowers have 3 stamens. The pistil in pistillate flowers is surrounded by a sac-like bract called a perigynium. The two or three style branches are exerted through an opening in the perigynium referred to as the mouth. Each perigynium is subtended by an unfused bract referred to as a pistillate scale. If there are two stigmas or style branches, the achene is lenticular (two sided); if there are three stigmas or style branches, the achene is trigonous (three sided).

Distribution:
Circumboreal.

Habitat:
Most sedges are found in moist areas by streams, open water or meadows. Some however, are found in woodlands or even in desert areas.

Other:
The genus, Carex , is extremely important in erosion control because of its extensive fibrous root system with or without rhizomes. They are important for grazing and in wild hay harvest for domestic livestock. While sedge achenes are edible, they are not normally utilized by Homo sapiens.

Important State References:
No information available at this time
Photos and Information written by Dr. Karl E. Holte,© 2002