Right, tony. I do feel as though 'shaving' a bit off each lateral surface of that long sloping 'back-cut' exposes more cambium for potential contact & callusing. Did a number of oaks & mulberries with that simple bark graft yesterday. Apples/pears - you can almost just throw the scions at the rootstock, or get them in the same room together, and you're virtually assured of success. I use a modification of that technique for most of the nut trees I graft(mostly pecans/hickories), especially when grafting relatively small-caliper scions onto rootstocks 2-4X their diameter - but instead of completely beheading the rootstock, I just cut about 3/4 of the way through, and break the top over, leaving it attached as a 'sap-drawer', then place my simple bark graft. Once the scion is pushing growth, I'll come back and snip off the 'hanging top' of the rootstock.

ltilton, yes, it's sufficient for as long as it lasts, but on large stock it's iffier as to how long that will be. I like a graft that I can leave alone as much as possible in the aftercare, and I don't like a lot of tape and tar and such uglifying the tree- just fussy, on my part! I've seen cleft grafts that are several years old that are still "open" or that have really gnarly callous formations covering them. It's hard to have full confidence in those. cousinfloyd, I used the term "cooperate" because sometimes you can do a graft one way but not another, because the wood's not ready for one, but is OK for the other. For example you might not be able to bud because the bark's not slipping well but you can still chip. Whip and tongue grafts depend on a certain suppleness to the wood that isn't so important in cleft grafting. To bark graft the bark must be slipping but if it's not, well, fall back on a chip or a cleft.

I've found that when regrafting virginiana rootstock when the previous graft, say of kaki, had been lost to a hard winter that often the rootstock cambium is in less than ideal condition. I believe this causes my percent of successful grafts to decrease and the vigor of the grafts that do to be low. In this scenario I would recommend instead of grafting immediately to such a rootstock, to allow the rootstock to sprout and once the green wood is of sufficient size later in the season, to use it as the grafting site. This strategy allows you to tap into the tree much lower than would otherwise be possible and so avoid the damaged portions of the rootstock. It also allows you to harness the considerable energy of these sprouts to allow for a vigorously growing graft, which although started later will soon outpace a graft made directly to the rootstock trunk.

Konrad, I wish you would start a new post with the pictures (f you have them). I have two dwarf rootstocks from trees that the grafts died due to girdling from rabbits; want to use some of the prunings from my standard trees to try to graft to those. Good pictures are so helpful.