Yellow Nutsedge

Plant Description: Yellow nutsedge is an erect, grass-like perennial, characterized by its shiny yellowish-green leaves, triangular stem, golden-brown flower head and shallow rhizomes (horizontal underground stems) that produce many nut-like tubers. Young seedlings are often confused with grasses. This species reproduces primarily by tubers and less often by seeds. Rhizomes help to enlarge patches.

Yellow nutsedge forms a complex, shallow underground system composed of fine fibrous roots, thin scaly rhizomes (horizontal underground stems), hard spherical tubers and basal bulbs. The leaves are light yellowish-green (4 to 12 inches long or longer, 1/8 to 1/2 inch wide) with a prominent mid-vein, a waxy surface and a gradually tapering, pointed tip. Leaves are arranged in 3's and form a sheath around the stem. Most leaves are produced toward the base of the plant.  Inconspicuous flowers are arranged into numerous, flat, narrow, straw-colored clusters within a branched, umbrella-shaped flower head at the top of the stem.

Flowering occurs from July to September. Seed germination begins in May. Tuber germination typically begins as soil temperatures reach about 54° F (in May), and shoots continue to emerge through mid-July. Tuber formation begins in late July and continues through the rest of the growing season.

Yellow nutsedge reproduces and spreads primarily by tubers, which are the only structures (besides seeds) that can survive the winter.