Interested in an "orange tree" hardy to zone 5? Then you may enjoy reading this article on osage orange trees written by About's Forestry Guide, Steve Nix. Okay, so osage orange trees do not produce real oranges that you can eat. But osage orange trees do bear not only terrific fall foliage, but also a showy fruit that the squirrels like. However, as Steve suggests, some of you may prefer the fruitless version.