Answer: These trees are typically pruned only to remove damaged or rubbing branches, or in some instances by a talented pruner to enhance the natural shape of the tree. If you prune strictly for size you may end up encouraging growth in the area you are trying to limit. Since this is a well established tree you might prefer to consult with a professionally trained and certified arborist who also has a true interest in this type of tree and can work with its natural shape to achieve the results you desire.
Fertilizer needs would be best determined based on the results of soil tests; if the tree is growing well,then there would be no need to change what you are doing presently. A qulaified arborist or your county extension should be able to help you with the tests and interpreting the results.
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