This is widely scattered across east-central states, but most common in the Midwest, and generally restricted to highly fertile soils on mesic to submesic sites (K, Schmitz & Carstens 2018). Uncertain records mapped here as open dots include a few that may come from planted trees, especially those within Appalachian regions (Gm, CW). Note that the correct spelling may still be dioica (Y). In the central Bluegrass, Short (1828-9) noted that Gymnocladus is "...peculiar to the forests of Canada and the western states of North America, in no portion of which is it more commonly met with, or seen in greater perfection than in the immediate neighbourhood of Lexington." Although this landscape is now mostly converted to farmland, the species survives well along woodland edges and fencerows, sometimes colonizing adjacent old fields. The plant is generally toxic to animals, although deer (J. Schaffer, pers. comm.) and rabbits (Pearce & Reineke 1943) can exhibit some local feeding preference. Also, pods of Gymnocladus are relished by cattle, who often consume them after they fall to the ground during late winter to spring, mostly late Feb to mid Apr (pers. obs. and Gm); some pods can stay on trees as late as mid-May during cold springs with delayed bud-break. Deposits of seeds can sometimes be found in old cattle barns (LC of ANDE, pers. comm.). Similar evidence suggests occasional dispersal by other mammals, including deer (pers. obs.) and racoons (T. Littlefield, pers. comm.). In addition to being generally dioecious, this tree is unusual in its lateral root suckering up to 5 m or more from original stems (especially in males). Maximum sizes for this species are often understated; forest-grown trees frequently reach 25-30 m tall in east-central states, with dbh of 5-10 dm; the national champion in HARR is 38 m tall and 10.7 dm dbh (Schmitz & Carstens 2018). Open grown trees tend to be shorter but with dbh up to 16-18 dm dbh.