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Yellow Nutsedge Cyperus esculentus
History and Impact
This plant is an extremely competitive invader of both cultivated and uncultivated lands, and is very difficult to control. As a Class A noxious weed, eradication is required in King County.
Biology and Morphology
Yellow nutsedge is a perennial sedge with glossy, triangular stems that grow from 6 to 30 inches tall. Most of the leaves grow from the base and are as long as, or longer than, the stem. Straw-colored to golden brown seed heads are surrounded by a whorl of leaf-like bracts.Yellow nutsedge reproduces by seeds, rhizomes, corn-like basal buds or tubers, the latter serving as the major means of spread. A single plant can form several thousand tubers per season under noncompetitive conditions. Dormant nutlets over-winter in the soil. Individual tubers contain numerous buds and can sprout several times before the food reserves are gone.
If you find yellow nutsedge in King County, please notify us through our online infestation form.
To find out where we have records of this weed in King County, use our interactive noxious weed map and search for yellow nutsedge.
Program offices are located at 201 S. Jackson St., Suite 600, Seattle, WA 98104. To contact a staff member at the King County Noxious Weed Control Program, please call 206-296-0290 or by reach them by email.
This plant is an extremely competitive invader of both cultivated and uncultivated lands, and is very difficult to control. As a Class A noxious weed, eradication is required in King County. 
Yellow nutsedge is a perennial sedge with glossy, triangular stems that grow from 6 to 30 inches tall. Most of the leaves grow from the base and are as long as, or longer than, the stem. Straw-colored to golden brown seed heads are surrounded by a whorl of leaf-like bracts.Yellow nutsedge reproduces by seeds, rhizomes, corn-like basal buds or tubers, the latter serving as the major means of spread. A single plant can form several thousand tubers per season under noncompetitive conditions. Dormant nutlets over-winter in the soil. Individual tubers contain numerous buds and can sprout several times before the food reserves are gone. 
for yellow nutsedge.