This is a widespread eastern species. Var. lasia Fern., with densely villous branchlets, has been distinguished in southern regions (F), including Ky. (M), but it has not been recognized in recent treatments (FNA 3, W). Compared to Carpinus, leaves of Ostrya differ in their downy lower surfaces (versus glabrous); and they are usually more coarsely serrate, with less distinction between large and small teeth (versus clearly double-serrate). Both species are relatively unpalatable to mammalian herbivores, due to high tannin content, and Ostrya is the least favored (e.g. Asnani et al. 2006, Bresette et al. 2012). Both may increase where browsing has been intense for several decades, but hungry deer can be persistant (Atwood 1941), and the ability of these plants to resprout following repeated damage may be relatively low (e.g. Collins & Carson 2003). Both species appear to have been called "ironwood" by early surveyors, but in later literature Carpinus became called "hornbeam" instead (e.g. Shaler 1884).