YELLOW NUTSEDGE, Cyperus esculentus L. 1, whole plant; 2, seed. Perennial, reproducing by seed and by tubers produced at the tips of scaly rhizomes. Root system fibrous. Stems erect, triangular, yellow green. Leaves 3-ranked, narrow, grasslike, basal. Flowers yellowish or yellowish-brown, small, arranged in narrow spikelets on umbel-like inflorescence. Seeds yellowish-brown, 3-angled, small, about 1/16 inch (1.5 mm) long, with blunt ends. Found primarily on low, damp soils. Often troublesome in cultivated fields and pastures, especially on low land. Usually considered a serious weed.