Western balsam poplar vs black cottonwood

Western balsam poplar and black cottonwood both are nouns.

Word	Noun	Adjective	Verb	Adverb
Western balsam poplar	Yes	No	No	No
black cottonwood	Yes	No	No	No

As nouns, Western balsam poplar and black cottonwood are synonyms defined as:

Western balsam poplar and black cottonwood: cottonwood of western North America with dark green leaves shining above and rusty or silvery beneath

Other synonyms of Western balsam poplar include Populus trichocarpa.

Western balsam poplar (noun)	black cottonwood (noun)
cottonwood of western North America with dark green leaves shining above and rusty or silvery beneath	cottonwood of western North America with dark green leaves shining above and rusty or silvery beneath
	North American poplar with large rounded scalloped leaves and brownish bark and wood