Ulmus thomasii Sarg.
Common Name: ROCK ELM, CORK ELM
Coefficient of Conservatism: 4
Coefficient of Wetness: 0
Wetness Index: FAC
Physiognomy: Nt Tree

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.

Locations

Antrim County
Benzie County
Charlevoix County
Genesee County
Gladwin County
Grand Traverse County
Gratiot County
Hillsdale County
Ingham County
Ionia County
Iron County
Isabella County
Kalamazoo County
Kent County
Lake County
Lenawee County
Macomb County
Mecosta County
Menominee County
Missaukee County
Monroe County
Newaygo County
Oakland County
Ontonagon County
Oscoda County
Saginaw County
St. Clair County
Tuscola County
Washtenaw County
Wayne County
Wexford County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. January 19, 2020. https://michiganflora.net/species.aspx?id=2752.