wool grass vs Scirpus

wool grass and Scirpus both are nouns.

Word	Noun	Adjective	Verb	Adverb
wool grass	Yes	No	No	No
Scirpus	Yes	No	No	No

wool grass (noun)	Scirpus (noun)
grass often cultivated for its long white-ribbed leaves and large plumes resembling those of pampas grass	rhizomatous perennial grasslike herbs
sedge of eastern North America having numerous clustered woolly spikelets