Yellow nutsedge Cyperus esculentus L.
Cyperaceae (Sedge family)
Rhizomatous perennial sedge.
Yellowish green, shiny, grasslike leaves are long and narrow, and distinctly ridged along the midvein, and they narrow to a long, sharp point. Leaves are mostly basal and alternate, and they point outward from the stem in three directions.
Erect, solid, up to 3-foot-tall stems are triangular in cross-section. Plants spread by wiry, scaly rhizomes and nutlike tubers produced at the rhizome tips.
Flowers and fruit
The seedhead consists of numerous yellowish brown spikelets, which occur in a terminal, umbrellalike cluster. Under each seedhead is a whorl of several long, leaflike bracts. The seed is enclosed in a single-seeded, three-angled, yellowish brown fruit with a blunt end.
Tubers, rhizomes and, very rarely, seeds.