Richard Carter, Valdosta State University, Bugwood.org

Family: Cyperaceae (Sedge Family)

Synonym(s):

Duration: Perennial

Habit: Grass/Grasslike

Listed by:
Invasive Plant Atlas of the US: 1
Federal Noxious Weed: 0
TDA Noxious Weed: 1
TPWD Prohibited Exotic Species: 0

Description: Grows in robust, loose clumps to up to 40 inches high; leaves are cross-sectionally V-shaped and glossy. Leaf bases are distinctly purplish-black. Culms (stems) are strongly 3-sided. The inflorescence is terminal and consists of 5 - 11 groups of densely clustered spikelets, which are greenish-white. Culms are connected by thick rhizomes.

History: Most likely introduced via rice agriculture and was first reported in Texas from Cameron County about 20 miles north of Brownsville in 1941 (Rosen et. al, 2006). Continues to spread especially along roadsides via mowing, flooding, and soil and equipment movement.

Biology & Spread: An aggressive seed producer; large plants can produce 1 million viable seeds/year. Seeds are readily transported by water. Will flower and fruit from June through November. Also reproduces vegetatively via fragmentation and budding of rhizomes.

Ecological Threat: Rapidly spreading from disturbed to natural areas. Once established, it outcompetes native grasses and sedges, threatening local plant biodiversity. Alters habitat for the endangered Attwater's prairie chicken. A potential pest to rice agriculture.

US Habitat: Thrives in disturbed, inundated soils. Will form monospecific stands in ditches, coastal prairies, low flatwoods, and fallow rice fields. Tolerant to various soil textures (sands to clays).

Distribution

US Nativity: Introduced to U.S.

Native Origin: South America

US States: AL, FL, GA, LA, MS, TX

Resembles/Alternatives: Alternatives include:
Big bluestem (Andropogon gerardii)
Sideoats grama (Bouteloua curtipendula)
Starrush whitetop (Rhynchospora colorata)

Management: Mechanical Mowing at 2-4 week intervals suppresses seed production. Machinery should be kept clean to prevent seed spread.

Chemical: A collaborative study between USDA-ARS, USGS-FCSC and USFWS show 2% solution of Glyphosate is expected to achieve 98% control when applied at a rate of 2 quarts/acre.

USE PESTICIDES WISELY: ALWAYS READ THE ENTIRE PESTICIDE LABEL CAREFULLY, FOLLOW ALL MIXING AND APPLICATION INSTRUCTIONS AND WEAR ALL RECOMMENDED PERSONAL PROTECTIVE GEAR AND CLOTHING. CONTACT YOUR STATE DEPARTMENT OF AGRICULTURE FOR ANY ADDITIONAL PESTICIDE USE REQUIREMENTS, RESTRICTIONS OR RECOMMENDATIONS. MENTION OF PESTICIDE PRODUCTS ON THIS WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.

Listing Source

Texas Department ofAgriculture Noxious Plant List
Texas Parks and Wildlife Department Prohibited Exotic Species
Invaders Program
Federal Noxious Weed
Union of Concerned Scientists
United States Forest Service Southern Research Station

Text References

Rosen, D.J., R. Carter and C.T. Bryson. 2006. The spread of Cyperus entrerianus (Cyperaceae) in the southeastern United States and its invasive potential in bottomland hardwood forests. Southeastern Naturalist 5:333-344. http://www.valdosta.edu/~rcarter/Rosen.Carter.Bryson.2006.pdf

Data Source

The Quiet Invasion: A Guide to Invasive Plants of the Galveston Bay Area.

https://www.invasive.org/eastern/other/ypentrflyer.pdf

Last Updated: 2024-01-30 by ARMO, TISI