sorrel tree vs sourwood

sorrel tree and sourwood both are nouns.

Word	Noun	Adjective	Verb	Adverb
sorrel tree	Yes	No	No	No
sourwood	Yes	No	No	No

As nouns, sorrel tree and sourwood are synonyms defined as:

sorrel tree and sourwood: deciduous shrubby tree of eastern North America having deeply fissured bark and sprays of small fragrant white flowers and sour-tasting leaves

Other synonyms of sorrel tree include Oxydendrum arboreum, titi.

sorrel tree (noun)	sourwood (noun)
Australian tree with acid foliage	deciduous shrubby tree of eastern North America having deeply fissured bark and sprays of small fragrant white flowers and sour-tasting leaves
deciduous shrubby tree of eastern North America having deeply fissured bark and sprays of small fragrant white flowers and sour-tasting leaves