silver birch vs European white birch

silver birch and European white birch both are nouns.

Word	Noun	Adjective	Verb	Adverb
silver birch	Yes	No	No	No
European white birch	Yes	No	No	No

As nouns, silver birch and European white birch are synonyms defined as:

silver birch and European white birch: European birch with silvery white peeling bark and markedly drooping branches

Other synonyms of silver birch include Betula pendula, common birch.

silver birch (noun)	European white birch (noun)
European birch with silvery white peeling bark and markedly drooping branches	European birch with silvery white peeling bark and markedly drooping branches