Greg Malone, the plant science program director, told me the weird objects were the fruit of the Osage orange tree. There isn't a nut inside, just a fleshy center and tiny seeds, he said.

yellow, and orange. Some tree species can express several of these colors simultaneously as the season progresses. All leaves start out in summer as green. This is because of the presence of a ...

The fruit of Osage orange, produced by female trees, also is a key identifying characteristic, as it resembles a large yellow-green-colored bumpy orange or a bumpy green apple. The fruit is four to ...