whispering bells vs California yellow bells

whispering bells and California yellow bells both are nouns.

Word	Noun	Adjective	Verb	Adverb
whispering bells	Yes	No	No	No
California yellow bells	Yes	No	No	No

As nouns, whispering bells and California yellow bells are synonyms defined as:

whispering bells and California yellow bells: viscid herb of arid or desert habitats of southwestern United States having pendulous yellow flowers

Other synonyms of whispering bells include Emmanthe penduliflora, yellow bells.

whispering bells (noun)	California yellow bells (noun)
viscid herb of arid or desert habitats of southwestern United States having pendulous yellow flowers	viscid herb of arid or desert habitats of southwestern United States having pendulous yellow flowers