Agropyron repens vs witchgrass

Agropyron repens and witchgrass both are nouns.

Word	Noun	Adjective	Verb	Adverb
Agropyron repens	Yes	No	No	No
witchgrass	Yes	No	No	No

As nouns, Agropyron repens and witchgrass are synonyms defined as:

Agropyron repens and witchgrass: European grass spreading rapidly by creeping rhizomes; naturalized in North America as a weed

Other synonyms of Agropyron repens include couch grass, dog grass, quack grass, quackgrass, quick grass, witch grass.

Agropyron repens (noun)	witchgrass (noun)
European grass spreading rapidly by creeping rhizomes; naturalized in North America as a weed	North American grass with slender brushy panicles; often a weed on cultivated land
	European grass spreading rapidly by creeping rhizomes; naturalized in North America as a weed