Japanese maple trees need pruning to remain healthy over time. Exactly how you prune your tree will depend on the type of tree you have. Some trees, like the Bloodgood Japanese maple, grow in an upright fashion. Other trees, like the Ornatum Japanese maple, grow in a weeping, globe-like form. The exact pruning technique for the two types of trees will differ. The upright should be pruned in an open form to encourage sunlight to penetrate the canopy. Weeping trees should be pruned to prevent the weeping branches from touching the ground.
Prune your tree from the bottom up and from the inside out. Walk around your tree frequently to see the effects on the overall shape of your tree.
Remove any larger, lower branches before continuing up the tree.
Cut out any dead or dying branches.
Remove any branches that cross to prevent damage to the bark, which could create a vector for a tree infection.
Trim excess twigs and branches beginning from the center of the tree and working your way out toward the ends. If pruning an upright growing tree, thin the branches to allow sun to reach the middle of the tree.