directive summer pruning cuts made as spring growth emerges. Summer pruning has proven to be the most effective way to define and keep a strong central leader in the long run.
In the first photo of pruning this tree, I pointed to a limb that needed pruning to release the leader to grow more vigorously. In the second pruning photo, the yellow arrow points to the same limb that needs removal back to the trunk. From this photo angle, you can see just how competitive that limb is towards the central leader and why it needs to be pruned out. Also, the green arrow points to a fork in the central leader. One half of that folk needs to be removed before it grows into a more difficult pruning problem.