General Description: Shiny, dark green, erect clump-forming winter annual with smooth leaves that is often purplish at the base. Grows 1 to 3 feet tall in seed head stage.
Seedling: The first leaf blade is long and narrow, oriented perpendicular with the soil surface. Leaves are rolled in the bud; auricles are present but may be absent on very young seedlings, and the ligule is membranous. Blades are about 50 times as long as wide, lack hairs, and have prominently raised veins. Sheaths are also smooth and often reddish at the base. Mature Plant: Auricles are narrow, long, and claw-like. Blades are long and tapered, glossy below and rough above, with prominent veins and smooth margins. Sheaths are rounded, and the collar is broad. Flowers and Fruit: The seedhead is a terminal spike. The spikelets are placed alternately along the flowering stem. The terminal spike consists of 10 to 20 florets and long awns. Spikelets only contain 1 glume. Distribution: Occurs throughout the United States. Crops Affected: Corn, Wheat, Soybean Animal Poisoning: None Similar Species: Perennial ryegrass is shorter with small or malformed auricles, spikelets with 6 to 10 florets, and is a perennial. Awns are often absent or greatly reduced. Italian ryegrass is more robust in habit than perennial ryegrass. Quackgrass also has awns and a seedhead that can look similar to that of ryegrass. However, quackgrass is a rhizomatous perennial with spikelets subtended by 2 basal bracts (glumes), whereas all species of ryegrass have only 1 basal bract.