California sagebrush vs California sage

California sagebrush and California sage both are nouns.

Word	Noun	Adjective	Verb	Adverb
California sagebrush	Yes	No	No	No
California sage	Yes	No	No	No

As nouns, California sagebrush and California sage are synonyms defined as:

California sagebrush and California sage: low ashy-grey California shrub

Other synonyms of California sagebrush include Artemisia californica.

California sagebrush (noun)	California sage (noun)
low ashy-grey California shrub	low ashy-grey California shrub