tulip poplar vs flowering tree

tulip poplar and flowering tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
tulip poplar	Yes	No	No	No
flowering tree	Yes	No	No	No

As nouns, flowering tree is a hypernym of tulip poplar; that is, flowering tree is a word with a broader meaning than tulip poplar:

tulip poplar: tall North American deciduous timber tree having large tulip-shaped greenish yellow flowers and conelike fruit; yields soft white woods used especially for cabinet work
flowering tree: any tree having seeds and ovules contained in the ovary

Other hypernyms of tulip poplar include angiospermous tree.

tulip poplar (noun)	flowering tree (noun)
tall North American deciduous timber tree having large tulip-shaped greenish yellow flowers and conelike fruit; yields soft white woods used especially for cabinet work	any tree having seeds and ovules contained in the ovary