September elm vs red elm

September elm and red elm both are nouns.

Word	Noun	Adjective	Verb	Adverb
September elm	Yes	No	No	No
red elm	Yes	No	No	No

As nouns, September elm and red elm are synonyms defined as:

September elm and red elm: autumn-flowering elm of southeastern United States

Other synonyms of September elm include Ulmus serotina.

September elm (noun)	red elm (noun)
autumn-flowering elm of southeastern United States	North American elm having rough leaves that are red when opening; yields a hard wood
	autumn-flowering elm of southeastern United States