white birch vs Betula pubescens

white birch and Betula pubescens both are nouns.

Word	Noun	Adjective	Verb	Adverb
white birch	Yes	No	No	No
Betula pubescens	Yes	No	No	No

As nouns, white birch and Betula pubescens are synonyms defined as:

white birch and Betula pubescens: European birch with dull white to pale brown bark and somewhat drooping hairy branches

Other synonyms of white birch include downy birch.

white birch (noun)	Betula pubescens (noun)
European birch with dull white to pale brown bark and somewhat drooping hairy branches	European birch with dull white to pale brown bark and somewhat drooping hairy branches