I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
If the tree was planted from a seed it is just not yet reached maturity which can take a few more years. If it is grafted tree then I would consider if it is receiving enough light. You don't need to prune it much at all. Just remove broken or crossing limbs and any hanging too low. The best pruning time is late winter but now is still okay.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
Q&A Library Searching Tips