 The glabrous young shoots become progressively corky-winged with age, and bear oblong to obovate leaves <8 cm long.The wind-pollinated apetalous perfect flowers form pendulous racemes which open in September and serve to distinguish the species from its compatriot, the cedar elm "U. crassifolia", with which it readily hybridizes.The samarae are oblong-elliptical, 10–15 mm in length, deeply divided at the apex, and ripen in November 

The species is highly susceptible to Dutch elm disease.