On a routine field inspection of a site in extreme southern Dunklin County, Missouri, Ulmus crassifolia Nutt. was found. This elm is new to the state (Steyermark 1963; Ginny Wallace, pers. comm.). Ulmus crassifolia is known from southwestern Tennessee, Arkansas, and southern Oklahoma, south to central and southern Texas and extreme northeastern Mexico, east to Louisiana and western Mississippi (Little 1979).