Answer: You didn't say what type of tree you're growing so I can only give general suggestions. Prune early this spring, just as new growth begins. You can shorten the branches by one-third to encourage a thick, dense canopy. Some trees look gawky in youth but develop into grand specimens as they age. Since your tree is fast-growing, you'll want to help the basic canopy structure be thick and sturdy by shortening the branches which will force new growth in the center of the canopy.
Best wishes with your landscape!
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