silk grass vs mountain rice

silk grass and mountain rice both are nouns.

Word	Noun	Adjective	Verb	Adverb
silk grass	Yes	No	No	No
mountain rice	Yes	No	No	No

As nouns, silk grass and mountain rice are synonyms defined as:

silk grass and mountain rice: valuable forage grass of dry upland areas and plains of western North America to northern Mexico

Other synonyms of silk grass include Indian millet, Oryzopsis hymenoides, silkgrass.

silk grass (noun)	mountain rice (noun)
valuable forage grass of dry upland areas and plains of western North America to northern Mexico	valuable forage grass of dry upland areas and plains of western North America to northern Mexico