Populus alba vs aspen poplar

Populus alba and aspen poplar both are nouns.

Word	Noun	Adjective	Verb	Adverb
Populus alba	Yes	No	No	No
aspen poplar	Yes	No	No	No

As nouns, Populus alba and aspen poplar are synonyms defined as:

Populus alba and aspen poplar: a poplar that is widely cultivated in the United States; has white bark and leaves with whitish undersurfaces

Other synonyms of Populus alba include abele, silver-leaved poplar, white aspen, white poplar.

Populus alba (noun)	aspen poplar (noun)
a poplar that is widely cultivated in the United States; has white bark and leaves with whitish undersurfaces	a poplar that is widely cultivated in the United States; has white bark and leaves with whitish undersurfaces