Quackgrass

Grass (Poaceae family):

Elytrigia repens (L.) Gould

EPPO code:

AGGRE

Other names:

Twitch, twitch grass, couch grass, quitch grass, scutch grass

Species information

Lifecycle:

Perennial.

Propagation:

Reproduces primarily by underground rhizomes, which produce new shoots when fragmented. Quackgrass also reproduces by seed, but less successfully.

Emergence:

Shoots will emerge from rhizomes throughout the season.

Habitat:

Common throughout Ontario, quackgrass is found in cultivated fields, pastures, lawns and gardens.

Competitiveness:

Agriculture and Agri-Food Canada research has shown that quackgrass densities of 20,000 plants/ac can result in a 15–18% yield loss in corn and soybeans.

Identification clues

Auricles:

Quackgrass auricles are whitish and clearly visible at the base of the leaf blade.

Ligule:

The Ligule is membranous, but very short and hard to see.

Leaf blade:

Leaf blades are generally hairless on both sides, sometimes fine hairy, especially the young ones.

Leaf sheath:

The leaf sheath and leaf sheath margins are generally hairless except for those at the base.

Stem:

Round

Seed heads:

Quackgrass’ seed heads are elongated, narrow spikes with two rows of spikelets, each containing 3–7 flowers.

Roots and underground parts:

Quackgrass produces numerous whitish-brown rhizomes that grow horizontally and can produce new shoots. Very fine fibrous roots grow from the rhizome nodes.

Often mistaken for

I know it's not Wire-stemmed muhly because quackgrass leaves have auricles, whereas those of wire-stemmed muhly do not. Also, wire-stemmed muhly has very wiry stems and short, thin leaves.