bencelest

I agree with Richard. If the cambial layer is gone all around the bark, the roots can not feed the leaves anymore so it will eventually die. Wrapping the bark with grafting tape will do no good either because the upper part of the tree has to be fed somehow.That's why in grafting you only leave 2 to 3 buds (max) because of limited supply of sap the host mother can supply. Bridging with another bark from another tree will work maybe if you will drastically cut the top tree and leave just enough length enough to the bridged bark to supply the food. That in itself is not guaranteed either. You'll have to wrap the grafted bark and most of the plant to protect it from the sun and bacteria. Just like you are grafting.
This is my opinion only and I must admit I am not an expert like Joe is.

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Banana Nut