American Elm - 100 Most Common North American Trees

Pest information courtesy of USFS Fact Sheets:

Pests: Many pests may infest American Elm, including bark beetles, elm borer, gypsy moth, mites, and scales. Leaf beetles often consume large quantities of foliage.
Diseases: Many diseases may infect American Elm, including Dutch elm disease, phloem necrosis, leaf spot diseases, and cankers. American Elm is a host for Ganoderma butt rot.

American Elm and Dutch Elm Disease
More on Dutch Elm Disease
More on Tree Insects and Disease