LPT - they are sometimes called horse apples or osage oranges. They are a brainy-looking lime green "fruit" that many people believe repel insects. In fact, they are sold around here for like $4 a pound in the fall to put in your basements. I was excited to find this tree and bring home a big bag to put around my basement foundation.
I did find at least one site that recommended against feeding hedge apples to rabbits. I was just curious, because the squirrels were eating them like crazy where we found them - would have been a really cheap source of fresh food over the winter if I could have collected them and used them as a treat throughout the winter. No go, though, not willing to take any chances with my bun bud Roscoe!