This February, I discovered that our plum hybrid trees have had uneven corky tumors near the root crowns. From doing research, I learned this is actually crown gall, a disease infected by bacteria enter through the openings of the roots and trunks. The tumors, also called galls, tend to grow on the roots and trunks and prevent transporting of nutrients throughout the tree. Mature trees may survive, but younger ones may lose vigor and die. Our plum hybrids are one-year trees that I bought as bare-roots from the same nursery.   Crown gall, removed from a stone fruit tree, can be as big as an egg Treatment I treated crown gall with 10% bleach. Since the Flavor King pluot got hit the hardest. I had to prune 90% of its roots, soaked it in diluted bleach for approximately one hour and replanted it at the same spot. The other plum hybrid trees were not that bad. I only saw crown galls above the soil and did not have to pull them out to prune the roots. I just removed the galls and po...