Fraxinus pennsylvanica vs red ash

Fraxinus pennsylvanica and red ash both are nouns.

Word	Noun	Adjective	Verb	Adverb
Fraxinus pennsylvanica	Yes	No	No	No
red ash	Yes	No	No	No

As nouns, Fraxinus pennsylvanica and red ash are synonyms defined as:

Fraxinus pennsylvanica and red ash: smallish American tree with velvety branchlets and lower leaf surfaces

Other synonyms of Fraxinus pennsylvanica include downy ash.

Fraxinus pennsylvanica (noun)	red ash (noun)
smallish American tree with velvety branchlets and lower leaf surfaces	smallish American tree with velvety branchlets and lower leaf surfaces