genus Salix vs Salix alba vitellina

genus Salix and Salix alba vitellina both are nouns.

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

genus Salix (noun)	Salix alba vitellina (noun)
a large and widespread genus varying in size from small shrubs to large trees: willows	European willow having greyish leaves and yellow-orange twigs used in basketry