Salix pyrifolia vs genus Salix

Salix pyrifolia and genus Salix both are nouns.

Word	Noun	Adjective	Verb	Adverb
Salix pyrifolia	Yes	No	No	No
genus Salix	Yes	No	No	No

Salix pyrifolia (noun)	genus Salix (noun)
small shrubby tree of eastern North America having leaves exuding an odor of balsam when crushed	a large and widespread genus varying in size from small shrubs to large trees: willows