Leaf:  Basal, simple; blades narrow, linear, grass like, v-shaped in cross section, 8 to 80 cm long, 3 to 10 mm wide, arranged in sets of 3, with parallel venation, tapering gradually to a sharp point; margin entire (no teeth); upper surface yellow to green, shiny, hairless; lower surface with prominent midrib; sessile.  

Flower:  Compound umbel of several airy spikes arising from the top of the single stem, 8 to 25 spikelets per spike, the inflorescence surrounded by 3 to 9 blade-like bracts, 1 or more bracts being longer than the spikes; each yellow-brown spikelet having 8 to 20 slender flowers 5 to 20 mm long and 0.7 to 0.8 mm wide, lacking both petals and sepals; appearing July through October.

Fruit:  3-angled achene enclosed in a thin covering, broader near the tip, tapering to a narrow, rounded base; 0.9 to 1.5 mm long, 0.5 to 0.8 mm wide; usually yellowish-brown, but ranging from tan to dark brown; seed small, narrow, oblong, blunt.

Stem:  Erect, stout, unbranched, solid; 3-sided, triangular in cross section; green; to 1 1/2 feet (0.5m) tall.  

Form:  Perennial monocot, slender, grass-like. 
 

Discussion

The genus name Cyperus is from the Greek kypeiros or the Latin cuperos, each being the name the Greeks and Romans called sedges.  The species name esculentus is from Latin and means "edible", referring to the tubers.  

Nutsedge leaves and tubers provide a food source for waterfowl, deer, turkeys, and hogs.  

A painting in one Egyptian tomb shows the tubers being weighed and the weight recorded.  Researchers also found instructions for grinding the roasted tubers and mixing them with honey.  In Egypt and the Mediterranean the tubers were often used in coffee and in chocolate. Their oil was used as an ingredient in perfumed soap and the tubers were used for food for nursing mothers.  The tubers are round and ridged, light-colored at first, but turning brown or black, and reported to be sweet-tasting.

The weedy variety of nutsedge is reportedly more fibrous to chew than the cultivated variety.  Weediness seems to be its most noted attribute in the United States.  Nutsedge uses its many tubers to store food for the sprouts it will produce in the future.  Each tuber has numerous buds and can sprout repeatedly.  Nutsedge is difficult to kill by mowing or physically pulling because those actions just remove the leaves and it will just sprout back up again.  Nutsedge is resistant to herbicides because the poisons only kill the shoot system, and more sprouts grow.  Thus, nutsedge is a pesky weed in agricultural fields, nurseries, and landscapes.  

Yellow nutsedge causes economic losses in agriculture.  It flourishes on irrigated acreage, competing with crops for nutrients and space.  The nutsedge tubers have been known to grow right into commercial potato tubers, causing the product to be rejected.  Nutsedge tubers have also passed through the sorting equipment with shelled lima beans, necessitating costly hand-sorting.

Distinguishing Characteristics

Nutsedge looks grassy and glossy yellowish-green with v-shaped troughs down the leaves, triangular stems, and numerous yellowish flowering spikelets growing from the sides of the stem.

Distribution

The plant is known in all 50 states of the U.S.  Yellow nutsedge generally occurs in disturbed in disturbed habitats, but can tolerate a wide range of soil types, primarily on low, damp soils; does not tolerate shade.
 

Images

Click each small picture to see a larger image. 

October,2003 SDO	October, 2003 AD	October, 2003 SDO
October, 2003 AD

Location

N 39.27971°    W -89.89033°    
Next to sidewalk in the northwest corner of a vacant lot next to McDonald's, West Main Street, Carlinville, Macoupin County, IL. 

Copyright

Photos © 2003 Alana Dixon and Shannon Duda-Orrill, Carlinville High School, linke@carlinvilleschools.net       
            

References

Knoble, Edward. 1980.  Field guide to the grasses, sedges, and rushes of the United States.  2nd revised ed.  Mildred E. Faust.  Dover Publications, Inc., New York.  83 pp. 

Brown, Lauren. 1979.  Grasses.  Houghton Mifflin Company, Boston.  240 pp.

Editorial Subcommittee of the Regional Technical  Committee of Project NC-10, K.P. Buchholtz, Chairman. 1954.  Weeds of the north central states [North Central Regional Publication No. 36, Circular 718  Feb.1954].  University of Illinois, Urbana.  239 pp.   

Stubbendieck, James, Geir Y. Friisoe, and Margaret R. Bolick.  1994.  Weeds of Nebraska and the Great Plains.  Nebraska Dept. of Agriculture, Bureau of Plant Industry, Lincoln.  589 pp.

Statewide Integrated Pest Management Program, University of California
http://www.ipm.ucdavis.edu/PMG/WEEDS/nutsedge.html

King County Noxious Weed Control Program, Washington Department of Natural Resources
http://dnr.metrokc.gov/wlr/lands/weeds/Yellnut.htm

Virginia Tech Weed Identification Guide
http://www.ppws.vt.edu/scott/weed_id/cypes.htm

United States Dept. of Agriculture
http://infosys.ars.usda.gov/Weeds/Nutsedge/Yellownutsedge.htm

State Noxious Weed Control Board, Washington State
http://www.nwcb.wa.gov/weed_info/yellownutsedge.html

Christien Malan and Alice Notten.  2003.  Kirstenbosch National Botanical Garden
http://www.plantzafrica.com/plantcd/cyperustex.htm

David W. Hall and Vernon V. Vandiver.  Institute of Food and Agricultural Services, University of Florida 
http://edis.ifas.ufl.edu/BODY_FW014

College of Agriculture, University of Kentucky
http://www.uky.edu/Agriculture/Agronomy/Weeds/yellow_nutsedge.htm

Deatra J. Sams.  Ethnobotanical Leaflets, Southern Illinois University Carbondale
http://www.siu.edu/~ebl/leaflets/nutsedge.htm

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