This tree grows in front of the Rand wall near the intersection of two sidewalks on the Rand/Sarratt side.

Osage orange is an example of a dioecious (i.e. individuals either only male or only female) species.  This particular tree is a female, but doesn't produce fruit every year.  In the fall, the strange, lumpy fruits may be found lying on the ground below female trees.

Horses are one of the few animals known to eat this fruit and potentially disperse its seeds.  Given that horses are not native to North America, it is likely that the species' original disperser (probably a large mammal) died out during the mass extinction that occurred soon after the arrival of humans in North America.  If it is true that this tree was dispersed by extinct mammals, it may have been saved from extinction by Native Americans who favored its wood for use in bows.  Later, European settlers spread it throughout the central U.S. when they planted it as thick hedges to keep in livestock - hence one of its common names: hedge apple.

Notice how the branches arch out and downward.  The inner bark has a distinctive orangish brown color.  Close examination of the twig will reveal small, sharp spines.