Penstemon davidsonii vs Penstemon

Penstemon davidsonii and Penstemon both are nouns.

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

Penstemon davidsonii (noun)	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