Cyperus virens

green flatsedge
Family

Cyperaceae

Leaf Arrangement

alternate, basal

Leaf Type

cauline, simple

Leaf Shape

linear

Growth Form

graminoid

Flower Color

inconspicuous

Flower Month

July - September

Height (meters)

0.2 - 1.1

Milky Sap

No

Armed/Unarmed

Unarmed

Origin

native

Lifespan

perennial

Growing Season

Warm season


Wetland Class

FACW

Wetland Coefficient of Conservatism

4

Prairie Coefficient of Conservatism

0

Field Characters

Basal leaves are up to 2 feet in length, about 1/4 inch wide at their base, abruptly narrowing to about 1/8 inch, then gradually tapering to a point. The leaves are stiff, point upward, and are hairless except for a fine mat of woolly-hairs near their base. The leaf blades appear warty due to lumps often found between the veins (Grelen and Hughes 1984). Very similar to C. pseudovegatus but has hooks, like minute sharks teeth, on the angles of the culms. Spikelets all green. Stem triangular, rough toothed. 2' tall. 5-9 spidery bracts over 12" long. 3-5 leaves at base of stem.

Cultural Information

Freshly harvested seeds are dormant, but after-ripening at 35 F (2 C) for 10-29 weeks breaks dormancy. In experiments by Justice, ninety percent of seeds stored at room temperature germinated, some seeds were viable after 4 years of storage, and none were viable after 7 years (Justice 1957, Andersen 1968). Seeds average approximately 2,400,000 seeds/lb.

Animal Use

Although it is common, it is unimportant as forage. The foliage is not readily eaten by cattle, and the seed apparently has little value for wildlife.

Natural History

Green flatsedge if found in moist places of Louisiana and eastern Texas. It is very abundant in southeastern Texas. It ranges from South America to North Carolina and the Gulf States. It is reported to be adventive in California (Correll and Johnston 1979).

Habitat

Marshes, ditches and depressions, abundant in disturbed moist places.