white poplar vs aspen poplar

white poplar and aspen poplar both are nouns.

Word	Noun	Adjective	Verb	Adverb
white poplar	Yes	No	No	No
aspen poplar	Yes	No	No	No

As nouns, white poplar and aspen poplar are synonyms defined as:

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

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

white poplar (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
light easily worked wood of a tulip tree; used for furniture and veneer