Top Grafts in Place
In this case a single relatively large cion has been placed at the end of each stock branch, so that the new head will have approximately the form of the original tree. Many orchard fruits do better on foreign roots, and this method of top grafting is a familiar horticultural procedure. In Mr. Burbank's orchards the grafted cions are usually new varieties to be tested.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 3 Chapter 5