Answer: I think you will find the following instructions helpful for the bearing apple trees (when it is eventually the right time of year to prune.) You may need to cut and paste the complete url to make it work correctly.
As far as the ornamental plum that is growing like a bush it may be a somewhat shrubby variety such as Prunus x cistena. On these, you can gradually remove lower branches over several years time to reveal a multi-trunked small tree with a rounded overall shape. Or, you will find that they become more tree-like as the trunk and branches thicken with maturity. It is better to prune these as little as possible because pruning causes open wounds that are invitations to pests and diseases. The following addresses pruning ornamental trees.
Good luck with your trees!
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