Answer: These trees are grafted so any growth from below the graft should be removed. This includes suckers from the ground and emerging leaves or twigs on the trunk if they occur below the graft. After that, pruning becomes quite complex. Pruning will shorten branches and cause additional future branching to occur at or near the cuts you make, so if the shape looks good and the tree is growing well, it may not need any pruning at all. If you are going to do any pruning, you should do it in the very early spring before growth begins. (You can also save the trimmings for a bouquet of forced pussy willow buds.) You might find Dr. Shigo's pruning instructions from the following site http://www.teleport.com/~pnwisa/shigo.html helpful if you decide your tree needs some shaping.
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