Colorado spruce vs silver spruce

Colorado spruce and silver spruce both are nouns.

Word	Noun	Adjective	Verb	Adverb
Colorado spruce	Yes	No	No	No
silver spruce	Yes	No	No	No

As nouns, Colorado spruce and silver spruce are synonyms defined as:

Colorado spruce and silver spruce: tall spruce with blue-green needles and dense conic crown; older trees become columnar with lower branches sweeping downward

Other synonyms of Colorado spruce include Colorado blue spruce, Picea pungens.

Colorado spruce (noun)	silver spruce (noun)
tall spruce with blue-green needles and dense conic crown; older trees become columnar with lower branches sweeping downward	tall spruce with blue-green needles and dense conic crown; older trees become columnar with lower branches sweeping downward