This is very close to what it looks like, almost identical except the cluster of little bits in the fruit. The photo's of that tree show a wavy pattern, this one has a bubble pattern...kind of like the blackberry. It's also full of milky white juice. Looks like milk. I couldn't find any reference on the net of the Cudrania tricuspidata having this milky white stuff inside. Any ideas? Anyone? I'm just dying to know for sure what this is :). Thanks everyone! Here is a link that might be useful:

Farm...WOW, thats alott of figuring.And a research project in it self. I'm assuming that when you ask where you can buy some...your meaning citrus trees? Harris citrus,Acorn Springs,Fourwind growers,Briteleaf ect..ect..ect..these are also mail order citrus nurserys.But depending on where you live you can go usually in the early spring and buy them. Sometimes places like even Home Depot has them for sale. And as far as weight & the largest of all,you do the math and the research, this would be a good study for you to do if your interested in growing citrus.I can probably name a few here,My guess for Limes would be the Bearss lime,and Lemon would be the Ponderosa,Orange would possibly be the Washington Navel...as for weight I'm stumped here! Like I said before,this is certainly a research project.LOL! Good luck,***Suzanne

I live in the same climate zone, in Oakland, and have several fruit trees, so I know that the following have a proven track record. Someone else suggested Feijoa Sellowiana, also called pineapple guava. The variety "Coolidge" grows well, fairly upright, has beautiful flowers and is self fruitful. The following 2 suggestions could work with thoughtful pruning, and love our climate, Santa Rosa plum or black mission fig. Or a dwarf Meyer lemon tree. And now is a great time to plant with the winter rains to help get the tree established. I recommend East Bay Nursery in Berkeley, they have a great selection of healthy fruit trees and a knowledgeable staff.

Sounds like a plum. Pictures of fruit and tree would help