I admit, I do not have a very green thumb. So here are my personal statistics on keeping food-bearing trees alive:
Citrus: 6 out of 6 trees still alive. These have been very hardy. 3 have been exposed to severe neglect by me not watering them for a month at a time in hot weather (90 to 104 degrees F). The lemon tree is the hardiest - it has grown very well.
Hazelnut: 3 out of 3 trees dead. I got these from the arbor day foundation. They looked like small sticks with a couple of roots on the bottom. I may have taken too long to plant these.
Peach: 1 out of 1 tree alive, but barely. This baby tree has been neglected of water for months at a time and was planted in the shade. Considering the circumstances, this tree has been very hardy.
Avocado: 2 out of 2 trees dead. I think one was water-logged by being planted in clay soil. I was too lazy to plant the other one, so it dried out completely in its pot.
Cherry trees: 1 out of 1 planted trees dead, but 2 out of 2 existing trees still alive. I don't think the baby tree I planted was able to survive the neglect of water. I also placed it in a spot where I used to keep chickens. The ground may have too much nitrogen from the chicken poop for the poor tree to survive.
Pecan: None planted, many keep popping up. Pecan trees seem to want to grow where I am at. I think there may be animals burying the nuts in my yard. I would love to have pecan trees if I had a larger piece of property. But for now, my property is too small and I know that at least two of my neighbors do not like the tall pecan trees. This may have something to do with the sticky substance produced by aphids. I agree that I do not want sticky stuff on my car or house. I also do not want a tree so high that it poses a large hazard to my home if it falls.
Bay: Every year I cut down at least a dozen trees that I think are Bay Laurel. I cut these trees because they grow tall very quickly.
So which are the hardiest trees that I planted at my home near Sacramento, California? I would say the lemon tree (and all the citrus trees) and the peach tree. These trees have done an excellent job so far of surviving my neglectfulness.