Sentence:  "Robinia", with its center of distribution in the southern Alleghany region, is represented by two <WSD>arborescent</WSD> and one frutescent species in the Atlantic and by one <WSD>arborescent</WSD> species in the Pacific region. 
Meaning of the word marked with <WSD> tags:  Like a tree; having a structure or appearance similar to that of a tree; branching.