Evening, it's also called Hedge and Osage Orange (Maclura pomifera). It's quite remarkable wood. Very dense, extremely resistent to bugs and disease. Fence posts can last 100 years and still be good when dug up. Apparently the original range was Oklahoma and parts of Texas. Transplanted and grown by the Osage Indians near their villages. Highly prized for bows, examples have been found in the Dakotas. My best shooting bows are made of osage.
Humorous exchange on an archery forum located here:
http://forums.eders.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=008000
Start with the 4th poster down, Silverado.
Wasn't sure it would be a good idea to copy the thing directly to our thread.
Gotta go now..