Turffiles:Weeds:Sedge, Annual

Info Sheet

Maint. Calendars

Articles

Presentations

Guides

Reports

Alerts

News

Printable PDF
(114.6 kB)

annual sedge Sedge, Annual

[Cyperus compressus L.]

DESCRIPTION

This species is one of the few sedge species that is a true annual. As a result, this sedge is easier to control than many other perennial sedges. Annual sedge has a very characteristic seedhead that tends to be relatively large compared to other sedges, and the seedhead is flattened with a toothed outline. Annual sedge tends to have a more "clumpy" appearance than other sedges particularly when it occurs in low densities. This sedge also tends to emerge later in the spring/summer than most other sedge species.

Characteristic	Description
Growth Season	summer annual weed
Seed Arrangement on Spikes	tightly bunched; seedhead clusters of flat green spikes on stalks
Seedhead Spikelet Shape	flattened
Tuber Type	none


annual sedge seedhead	annual sedge stem cross section

Note: Still not sure this is the right weed? The Turf & Weed Identification Decision Aid may help. Check the TurfFiles glossary for definitions of unfamiliar terms.

CULTURAL CONTROL

This species is one of the few sedge species that is a true annual. As a result, this sedge is easier to control than many other perennial sedges. This sedge also tends to emerge later in the spring/summer than most other sedge species. Sedges are weeds that resemble grasses but unlike grasses, sedges have three-sided or triangular stems. It is important to properly distinguish sedges from grasses because management is totally different. Sedges are plants that thrive in wet or poorly drained soils but can survive in areas that are not wet. Because of frequent irrigation in highly maintained turf, sedges often thrive in the turfgrass environment. Sedges often become established in wet areas and spread to other areas that are not poorly drained or wet areas. Therefore, it is important to recognize areas where sedges can become established and prevent spread of these sedge species to other areas of the golf course or landscape.

CHEMICAL CONTROL

Several preemergence crabgrass herbicides will partially control this weed; however, effective control usually involves postemergence applications of arsonate herbicides such as MSMA or sulfonylurea herbicides such as Monument or Certainty. However, MSMA may be phased out in 2009.

*Preemergence herbicides:*

Herbicide	Tolerant Turfs ⁽¹⁾	Average Efficacy Rating⁽²⁾	Range of Trial Efficacy Values, %	Number of Trials	Products ⁽³⁾
metolachlor	ba, be, c, sa, z	G		0	Pennant Magnum
oxadiazon^,*	bc, be, bk, f, r, sa, z	G		0	Quali-Pro Oxadiazon, Ronstar

*Postemergence herbicides:*

Herbicide	Tolerant Turfs ⁽¹⁾	Average Efficacy Rating⁽²⁾	Range of Trial Efficacy Values, %	Number of Trials	Products ⁽³⁾
bentazon	ba, bc, be, bk, c, f, sa, z	G		0	Basagran T/O
halosulfuron	ba, bc, be, bk, c, f, r, sa, z	G		0	SedgeHammer
imazapic**	c	G		0	Plateau
imazaquin	be, c, sa, z	G		0	Image
MSMA***	be, r	G		0	MSMA (various brands)

*	For use only by or under the supervision of a certified applicator, or by commercial nursery, turf, and landscape personnel.
**	Not for application to residential lawns.
***	MSMA may be phased out in 2009.

*Footnotes:*
(1)	*Turfgrass Codes:*
	ba	bahiagrass
	bc	bentgrass, creeping
	be	bermudagrass
	bk	bluegrass, Kentucky
	c	centipedegrass
	f	fescue, tall
	r	ryegrass, perennial
	sa	St. Augustinegrass
	z	zoysiagrass
	blank	No turfgrass in the database is completely tolerant. Check label to see if chemical can be used at a reduced rate or during the dormant season on your turfgrass.
(2)	*Efficacy Ratings:*
	E	excellent control (90 to 100%)
	G	good control (80 to 90%)
	F	fair control (70 to 80%)
	Efficacy ratings are based on herbicide trials performed by weed scientists at North Carolina State University between 1997 and 2007. The number of trials included in the efficacy ratings is displayed in the next-to-last column. The higher this number, the more confidence can be placed in the efficacy values. Trials may have involved sequential applications of one or more chemical. Details of individual trials (herbicide rates, dates of application, environmental conditions at time of application, etc) can be viewed on the TurfFiles web site, through the Turf Weed Management Decision Aid. Efficacy ratings for chemicals lacking trial data are from “Pest Management Strategic Plan for Turfgrass in the Southern United States,” summary of a workshop for turf experts from multiple universities held in Griffin, GA in October, 2004 and sponsored by the Southern Region Integrated Pest Management Center.
(3)	Recommendations of specific chemicals are based upon information on the manufacturer's label and performance in a limited number of trials. Because environmental conditions and methods of application may vary widely, performance of the chemical will not always conform to the safety and pest control standards indicated by experimental data. The order in which brand names are given is not an indication of a recommendation or criticism.
	Recommendations for the use of agricultural chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services does not imply endorsement by North Carolina State University or discrimination against similar products or services not mentioned. Other brand names may be labeled for use on turfgrasses. Individuals who use agricultural chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact your county's Cooperative Extension agent.

© North Carolina State University. This information sheet was prepared by Fred Yelverton, Bridget R. Lassiter, Gail G. Wilkerson, Leon Warren, Travis Gannon, Jenifer J. Reynolds, and Gregory S. Buol. Department of Crop Science, College of Agriculture & Life Sciences, North Carolina State University. Prepared July 15, 2008. Available on-line at www.turffiles.ncsu.edu. This publication was made possible through a grant provided by the Center for Turfgrass Environmental Research & Education (CENTERE) whose purpose is to support worthwhile projects that will benefit both the private sector and the public, and protect the environment.

KEYWORDS FOUND IN THIS ARTICLE: