This large, thorny tree grows up to 90 feet tall. Young trees sometimes have red thorns and a smooth bark (B). Mature trees have brown thorns and scaly bark ridges curving outward (C). It has twice (bipinnately) compound leaves with 14-20 rounded leaflets (A). By October the leaves on the ground turn yellow (as whole leaves or single leaflets – as shown in image (G). The fruit is a flat, 6-16 inch long twisted seed pod, first yellow, then dark brown, often remaining on the tree well into winter (A,D,E). Trunks, branches and twigs exude a sticky resin during the summer (F). The related Kentucky Coffee-Tree (Gymnocladus dioica) has similar bark but lacks thorns, has pointed leaflets and thick seed pods.