Making Multi-Grafted Apples
This is obviously a complex issue. I have more scions than I have room for as single trees- not that I'm complaining. My goals are to build ideally healthy trees that are fairly balanced. I know to use similar vigor and pollination times. I'll use 3 or 4 varieties per tree. My goal is less about high production and more about discovering varieties.
My questions stem (I know)on when to use the various methods. I guess bark or cleft is the choice when doing serious limb removals. However I am wondering how to add onto a still desired 4 year tree: whip and tongue best when possible? Am I limited to the higher portion of the tree due to vigor? I'm guessing it is easiest to multi bud on a younger rootstock.
Also does anyone know of a good resource to figure this out? Thanks!