Removal of branches that what to revert back to green.
Propagation
grafting, will not come true from seeds
Author's Notes
This plant wants to revert back to all green. These green branches need to be removed or within a few years the tree will turn to entirely green. I have seen this happen on more than one occasion.
Notes & Reference
#01-Manual of Woody Landscape Plants (Michael Dirr)
#3-Hillier Manual of Trees and Shrubs