Scientific Name: Arrhenatherum elatius

Common Name: tall oatgrass

Other Common Names: false oatgrass, tall meadow oat, onion couch, tuber oat-grass

Habit: A perennial bunch-type grass that can grow 3 to 5 ft tall

Leaves: Leaf blades can be up to 12 inches long and 2 to 12 mm wide, are flat, hairless, and rough to the touch. The leaf has a short membranous ligule (1.5 to 2 mm), and the leaf sheaths are hairless.

Identifying Characteristics: Tall oatgrass, is a perennial, cool-season bunchgrass generally grown in Europe where it once was a component of the grasslands. Culms are erect, from 3 to 5 feet tall. It is one of the most drought tolerant cool-season grasses.

Flower Seed Head: Seed heads are narrow panicles 3 to 10 inches long and up to 2 inches wide with long, twisted, angled, exposed awns.

Seed Fruit: Seed grain are yellowish and hairy approximately 3.5 mm long with an elliptical shape

Where Found: Tall oatgrass has been introduced into the United States from Europe. It can establish in meadows, fields, open ground, waste places, and roadsides from south to Georgia, Louisiana, New Mexico, and California. Adapted to excessively drained low fertility soils.

  • Life cycle: perennial

  • Plant type: Grass

  • Auricle: not present

  • Plant family: Poaceae

  • Leaf arrangement: rolled in bud

  • Hair surface: hairs from base to tip

  • Ligule: membrane

  • Length: 1-2 mm

  • Seed head: panicle

  • Width: 6 to 15 mm; less than 5 mm

  • Grass stem: flat or oval