yellow pine vs pine tree

yellow pine and pine tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
yellow pine	Yes	No	No	No
pine tree	Yes	No	No	No

As nouns, pine tree is a hypernym of yellow pine; that is, pine tree is a word with a broader meaning than yellow pine:

Other hypernyms of yellow pine include pine, true pine.

yellow pine (noun)	pine tree (noun)
any of various pines having yellow wood	a coniferous tree
hard yellowish wood of a yellow pine