hagberry tree vs bird cherry

hagberry tree and bird cherry both are nouns.

Word	Noun	Adjective	Verb	Adverb
hagberry tree	Yes	No	No	No
bird cherry	Yes	No	No	No

As nouns, bird cherry is a hypernym of hagberry tree; that is, bird cherry is a word with a broader meaning than hagberry tree:

hagberry tree: small European cherry tree closely resembling the American chokecherry
bird cherry: any of several small-fruited cherry trees frequented or fed on by birds

Other hypernyms of hagberry tree include bird cherry tree.

hagberry tree (noun)	bird cherry (noun)
small European cherry tree closely resembling the American chokecherry	any of several small-fruited cherry trees frequented or fed on by birds