genus Salix vs Salix alba sericea

genus Salix and Salix alba sericea both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Salix	Yes	No	No	No
Salix alba sericea	Yes	No	No	No

genus Salix (noun)	Salix alba sericea (noun)
a large and widespread genus varying in size from small shrubs to large trees: willows	North American willow with greyish silky pubescent leaves that usually blacken in drying