How to Prune Siebold's maple?
Little pruning is needed. Remove diseased, damaged, crowded or crossing shoots and unwanted growth. If needed, Prune only from late autumn to midwinter.

Siebold's maple · Acer sieboldianum
Grow in fertile, moist but well-drained soil in sun or partial shade. See tree cultivation for further advice
Little pruning is needed. Remove diseased, damaged, crowded or crossing shoots and unwanted growth. If needed, Prune only from late autumn to midwinter.