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, grravelly or rocky, calcareous settings.
Vegetative specimens often cannot be 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, U. thomasii has a distinctive form with a narrow crown and strongly downturned, corky-winged lower branches.