Penstemon davidsonii vs genus Penstemon

Penstemon davidsonii and genus Penstemon both are nouns.

Word	Noun	Adjective	Verb	Adverb
Penstemon davidsonii	Yes	No	No	No
genus Penstemon	Yes	No	No	No

Penstemon davidsonii (noun)	genus Penstemon (noun)
mat-forming plant with blue and lavender flowers clustered on short erect stems; British Columbia to northern California	large genus of subshrubs or herbs having showy blue or purple or red or yellow or white flowers; mostly western North America