 Considered closely related to the Large-fruited Elm "U. macrocarpa", it is distinguishable from that species by its mottled, flaking bark and smaller leaves.The leaves, on 3–8 mm petioles, are obovate, < 10 cm long by 5.5 cm wide, caudate at the apex, with simply to doubly serrate margins, and densely pubescent when young; the leaves turn a rich gold in autumn.The perfect wind-pollinated apetalous flowers are produced on second-year shoots in March–April; the large < 35 mm diameter samarae appear from April to May.