northern pitch pine vs Pinus rigida

northern pitch pine and Pinus rigida both are nouns.

Word	Noun	Adjective	Verb	Adverb
northern pitch pine	Yes	No	No	No
Pinus rigida	Yes	No	No	No

As nouns, northern pitch pine and Pinus rigida are synonyms defined as:

northern pitch pine and Pinus rigida: large three-needled pine of the eastern United States and southeastern Canada; closely related to the pond pine

Other synonyms of northern pitch pine include pitch pine.

northern pitch pine (noun)	Pinus rigida (noun)
large three-needled pine of the eastern United States and southeastern Canada; closely related to the pond pine	large three-needled pine of the eastern United States and southeastern Canada; closely related to the pond pine