Should I prune these vertical branches on young plum tree?
The plum tree in attached picture was planted last summer. It didn't have too many long branches but I still pruned it this spring to try and get an open center. They really took off and now I have some nice branches. However, there are a few, as you can see in picture, that are growing straight up.
Is it OK to prune those so the energy goes into growing the lateral branches?