Should i wait for the leaves to fall of a tree i want to transplant?

When a tree goes through the healthy process of losing it's leaves, it is entering dormancy. This means that the tree is resting; it's sap is slowing down, therefore the leaves are dying. This is a good time to transplant because there is not the uptake from the roots; the tree is not putting it's energy into growth. By transplanting in the fall, there is less interruption to the growth process. This also means that there is the entire winter for the tree to have adjusted to it's new home and will be ready to grow more quickly than if it were transplanted in spring.