Erect, sometimes tufted perennial to 1.2 m tall, with extensive rhizomes . Quackgrass is a highly competitive, noxious agricultural weed of cool temperate regions nearly worldwide. It can significantly reduce crop yields, and seed contamination of seed grain crops reduces the value of the harvest.
Plants are highly variable with many regional biotypes.
Introduced from Eurasia. Develop rhizomes in the 6-8 leaf stage. Leaf characteristics resemble those of mature plants, except blades are usually 2-3 mm wide and auricles may be undeveloped. Leaves rolled in bud. Sheaths open, glabrous or covered with soft, short hairs.