silk grass vs silkgrass

silk grass and silkgrass both are nouns.

Word	Noun	Adjective	Verb	Adverb
silk grass	Yes	No	No	No
silkgrass	Yes	No	No	No

As nouns, silk grass and silkgrass are synonyms defined as:

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

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

silk grass (noun)	silkgrass (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