California black oak vs Quercus kelloggii

California black oak and Quercus kelloggii both are nouns.

Word	Noun	Adjective	Verb	Adverb
California black oak	Yes	No	No	No
Quercus kelloggii	Yes	No	No	No

As nouns, California black oak and Quercus kelloggii are synonyms defined as:

California black oak and Quercus kelloggii: large deciduous tree of the Pacific coast having deeply parted bristle-tipped leaves

California black oak (noun)	Quercus kelloggii (noun)
large deciduous tree of the Pacific coast having deeply parted bristle-tipped leaves	large deciduous tree of the Pacific coast having deeply parted bristle-tipped leaves