Quack Grass, or Couch Grass, a spreading perennial weed. It is also called quick grass, quitch grass, and witchgrass. Quack grass makes good pasture but is hard to eradicate from cultivated fields. Long underground runners send down roots at every joint and make quack grass one of the most troublesome weeds known. The runners also send up new plants at every joint.

Quack grass is Agropyron repens of the family Gramineae.