Coefficient of Conservatism:
Coefficient of Wetness:
ROCK ELM, CORK ELM
R. W. Smith
Mixed hardwood forests and moist rich forests along rivers, sometimes in drier, gravelly or rocky, calcareous settings.
Vegetative specimens often cannot be easily distinguished from essentially smooth-leaved plants of Ulmus americana unless the characteristic corky-ridged bark is present. Furthermore, sprout leaves of rock elm can be scabrous above. The inflorescence has an elongate axis, almost racemose, whereas the flowers in our other species are more densely clustered.
When growing in the open, Ulmus thomasii has one of the most distinctive winter silhouettes of any native tree. The crown is narrow, more or less cylindrical, with most of the lower branches especially, short, strongly downturned, and corky-winged.