Picea rubens vs eastern spruce

Picea rubens and eastern spruce both are nouns.

Word	Noun	Adjective	Verb	Adverb
Picea rubens	Yes	No	No	No
eastern spruce	Yes	No	No	No

As nouns, Picea rubens and eastern spruce are synonyms defined as:

Picea rubens and eastern spruce: medium-sized spruce of eastern North America; chief lumber spruce of the area; source of pulpwood

Other synonyms of Picea rubens include red spruce, yellow spruce.

Picea rubens (noun)	eastern spruce (noun)
medium-sized spruce of eastern North America; chief lumber spruce of the area; source of pulpwood	medium-sized spruce of eastern North America; chief lumber spruce of the area; source of pulpwood