tree tobacco vs tobacco plant

tree tobacco and tobacco plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
tree tobacco	Yes	No	No	No
tobacco plant	Yes	No	No	No

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

tree tobacco: evergreen South American shrub naturalized in United States; occasionally responsible for poisoning livestock
tobacco plant: aromatic annual or perennial herbs and shrubs

Other hypernyms of tree tobacco include tobacco.

tree tobacco (noun)	tobacco plant (noun)
evergreen South American shrub naturalized in United States; occasionally responsible for poisoning livestock	aromatic annual or perennial herbs and shrubs