Hi all! I have a Santa Rosa plum that I grew in a container for a year, and then this spring, transplanted it to the ground. Now that we're coming up on fall, it seems to be having a burst of new growth, which looks very different from the old growth. Most notable is the base, where there is one shoot that looks totally different from the rest of the tree. The old leaves are much smaller, mostly oval, serrated, and about 1-1.5" long. On this new shoot, the leaves are still serrated, more pointy than oval, and up to 3.5" long. The funny thing is, I don't see any signs of the tree being grafted, but I'm guessing it must be? And now it's growing from the root stock? But there's also quite a bit of new growth in the rest of the tree, too, and it doesn't look exactly like the new shoot I just described, OR the old growth, so I don't know what to make of it. I've mostly been a vegetable and ornamental gardener, so this is really my first experience with planting a tree. Any guidance? I'm thinking I should probably prune the shoot at the base of the tree? What about the other new growth? And out of curiosity, does the shoot that I described hint to anyone what the root stock is? Thanks!