Can you believe this? Joe Real of Davis, California, has successfully grafted 81 different citrus fruits on a single rootstock. 81-in-1!! His monster tree includes bergamot, Australian finger lime, honey mandarin, moro blood orange, star ruby grapefruit, nippon orangequat, seedless lemon, valencia orange, clementine nour, centennial variegated kumquat, delfino blood orange, lima acidless orange, dream navel, eureka lemon, Rio red grapefruit, and Washington navel fruits, to name but a few. You can read the full list on www.citrus.forumup.org/post-26473-citrus.htm. (If you want to see his photos, though, you must register and login).