Fraxinus oregona vs Oregon ash

Fraxinus oregona and Oregon ash both are nouns.

Word	Noun	Adjective	Verb	Adverb
Fraxinus oregona	Yes	No	No	No
Oregon ash	Yes	No	No	No

As nouns, Fraxinus oregona and Oregon ash are synonyms defined as:

Fraxinus oregona and Oregon ash: timber tree of western North America yielding hard light wood; closely related to the red ash

Other synonyms of Fraxinus oregona include Fraxinus latifolia.

Fraxinus oregona (noun)	Oregon ash (noun)
timber tree of western North America yielding hard light wood; closely related to the red ash	timber tree of western North America yielding hard light wood; closely related to the red ash