The Collaborative International Dictionary
Quitch grass \Quitch" grass`\ (kw[i^]ch" gr[.a]s`). [Properly quick grass, being probably so called from its vigorous growth, or from its tenacity of life. See Quick, and cf. Couch grass.] (Bot.) A perennial grass ( Agropyrum repens) having long running rootstalks, by which it spreads rapidly and pertinaciously, and so becomes a troublesome weed. Also called couch grass, quack grass, quick grass, twitch grass. See Illustration in Appendix.
Wiktionary
n. (alternative form of quackgrass English)
WordNet
n. European grass spreading rapidly by creeping rhizomes; naturalized in North America as a weed [syn: dog grass, couch grass, quackgrass, quick grass, witch grass, witchgrass, Agropyron repens]
Usage examples of "quack grass".
Maude flung a piece of quack grass into a bushel basket and turned.
Two successive crops are enough to reclaim land that has been abandoned because of Canadian thistles or quack grass.
And look at them gardens where nobody ever finds any weeds or quack grass anymore.