shagbark vs hickory tree

shagbark and hickory tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
shagbark	Yes	No	No	No
hickory tree	Yes	No	No	No

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

shagbark: North American hickory having loose grey shaggy bark and edible nuts
hickory tree: American hardwood tree bearing edible nuts

Other hypernyms of shagbark include hickory.

shagbark (noun)	hickory tree (noun)
North American hickory having loose grey shaggy bark and edible nuts	American hardwood tree bearing edible nuts