prickly pine vs pine tree

prickly pine and pine tree both are nouns.

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

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

prickly pine: a small two-needled upland pine of the eastern United States (Appalachians) having dark brown flaking bark and thorn-tipped cone scales
pine tree: a coniferous tree

Other hypernyms of prickly pine include pine, true pine.

prickly pine (noun)	pine tree (noun)
a small two-needled upland pine of the eastern United States (Appalachians) having dark brown flaking bark and thorn-tipped cone scales	a coniferous tree