silver spruce vs Colorado blue spruce

silver spruce and Colorado blue spruce both are nouns.

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

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

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

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

silver spruce (noun)	Colorado blue 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