dwarf elm vs Ulmus pumila

dwarf elm and Ulmus pumila both are nouns.

Word	Noun	Adjective	Verb	Adverb
dwarf elm	Yes	No	No	No
Ulmus pumila	Yes	No	No	No

As nouns, dwarf elm and Ulmus pumila are synonyms defined as:

dwarf elm and Ulmus pumila: fast-growing shrubby Asian tree naturalized in United States for shelter or ornament

Other synonyms of dwarf elm include Chinese elm, Siberian elm.

dwarf elm (noun)	Ulmus pumila (noun)
fast-growing shrubby Asian tree naturalized in United States for shelter or ornament	fast-growing shrubby Asian tree naturalized in United States for shelter or ornament