Many deciduous trees can be defoliated in May or June.  This process involves removing all the leaves of the tree. The tree responds with a flush of new growth which increases the number of twigs (ramification).  Japanese maples are unusual for deciduous trees in that they do not respond well to defoliation.  Maples can be semi-defoliated however.  In this case, only a few of the largest leaves are removed which gives more light to the underlying leaves. Wire scars heal very slowly if at all, and the best way to deal with this was to cut the branch off.

Wiring deciduous trees is best done in the early summer when the big flush of spring growth is over and the branches are growing more slowly.  This way the wire can stay on the tree longer.  Wiring before the flush of growth in the spring means that the branches are rapidly expanding and wire scarring is far more likely. An added advantage of wiring in the early summer for trees amenable to defoliation is that the branches are more clearly seen without the distraction of leaves.