Twigs are orange-brown with a zigzag shape and have sharp axillary spines on vigorous juvenile growth. These spines may be infrequent or absent on mature, slow-growing trees, but will return on sprouts from such trees. Leaves are alternate, entire, shiny, ovate or ovate-lanceolate, and long pointed at the tip. Staminate and pistillate flowers are born on separate plants. Flowers are tiny.
Staminate flowers form short clusters and pistillate flowers are crowded into spherical heads.
The multiple fruit is large, spherical, and fleshy. These fruits are hazardous during abscission in late September to early November, and workers should wear hardhats around female trees. Osage orange should be accurately identified before attempting any control measures. It was introduced early into Missouri to be used for windbreaks, railroad ties, and for fencing cattle pastures. Osage orange frequently escapes from hedgerows.