Common: Common Couch, Twitch, Quick Grass, Quitch Grass, Dog Grass, Quackgrass, Scutch Grass, Witchgrass
Found in all 50 United States with the exception of Louisiana, Alabama, Florida, Georgia, South Carolina, and Hawaii
Couch/Quack Grass grows rapidly using creeping rhizomes. The leaves are flat and hairy with upright flower spikes. The leaves are linear, 8-16 inches long, and 1-3.5 inches broad at the base of the plant. The leaves become smaller up the stem. The flower spike is 4-12 inches long, with spikelets containing three to eight florets. It flowers late June through August. The foliage is useful to grazing mammals. Couch/Quack Grass does not tolerate long, hot summers, with optimum temperatures for growth being between 68 and 77 degrees Fahrenheit and no growth occurring above 95 degrees Fahrenheit or below 35 degrees Fahrenheit.