I just bought a cane made from the Cholla cactus. Very strong and light. I also found this site that has good pics of canes made of unusual materials. First page is the jersey cabbage and goes on for several pages.
http://www.canesegas.com/materials/1.jersey.cabbage.cane.html
http://www.canesegas.com/materials/1.jersey.cabbage.cane.html