I agree with Dax. One other possibility is to small cut in the cambium (notch?
nick?) above the branch to simulate apical dominance. This could be a good option if you have other grafts higher in the tree that you don't want to lose.
Found one more take, so that's 65%.....hoping for 1 more to get me over 70%
Here's a pic of some of the rootstock suckers. I'll need to be careful to let them go fully dormant this winter before moving them. I transplanted a bunch last year, but was a few days early, as their leaves hadn't dropped off. A few died and most that lived are coming back from the roots.
They continue to look good. I counted 6 apparent takes, where there are multiple leaves forming. Unlike peaches, I haven't seen grapes fail after this point. Of course, I've gotten very few grapes to the point, so it is almost uncharted territory for me.
There are also several others which look promising.
Over the last two weeks I lost 2 multi-graft trees. I'm not sure what did them in, but it seems like the more time and effort you put into creating a franken-tree, the more likely something will kill it. In addition to the apple and sour cherry I just lost, the biggest multi-graft apple died last year.
The apple which just died had 50 grafts on it, which covered 22 varieties. What really hurts is that this was the tree that I've grafted my seedlings to. After I had successful takes, I don't think I worried too much about them. I think I have a couple planted out at rentals, but some may be languishing (or dead) in a pot somewhere. And the whole goal of grafting them was to speed up fruiting. It wasn't working so well, as everything else on the tree flowered, except the 5 seedlings.
It's possible that a virus killed it. The tree could be on G16 (which is sensitive), but I'm not really, as it was mislabeled (large red apple, not Pome Gris). I did try to be careful what I put on there (mostly seedlings, Kaz apples, and modern disease resistant ones).
The sour cherry which died was the NorthStar which I was grafting over this spring. I'm not sure what killed it, but I'm not that sorry to see it go- it hasn't been productive, so I wanted something to change- preferable to make it productive with a different variety, but this is an OK outcome, as I can reclaim the space.
I did check out some of the bark grafts I made on it this spring and was surprised how well they healed. They stuck out a bit, but it was quite strong. I eventually snapped it off, but it took quite a bit of force and didn't break cleanly at the union, instead leaving part of the branch with the trunk.
So, maybe I shouldn't put so many grafts on a single tree. Not only is it like putting too many eggs in a basket, but it increases the chances of the basket to break.
Of course, within an hour of thinking of this, I was adding (TBuds) another peach variety to a tree which already has several (Doh), without even realizing what I was doing...I'm going to strive to only graft 3 varieties per tree max. Maybe.
For now, I've pruned the small branches back to the main structure on both dead trees. I've planted pole beans around both, so they can become trellis, at least for the rest of this growing season.