yellow spruce vs red spruce

yellow spruce and red spruce both are nouns.

Word	Noun	Adjective	Verb	Adverb
yellow spruce	Yes	No	No	No
red spruce	Yes	No	No	No

As nouns, yellow spruce and red spruce are synonyms defined as:

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

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

yellow spruce (noun)	red 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