Was it a cleft graft that you made? Have seen this many times on my own trees with cleft grafts espically on m111. I have not noticed any damage or weaker unions from it.

It's a tree I ordered, probably a 2 year old (however it had a few apples hanging from it so may be older) and the root stalk 'as usual' was not listed.
Thanks!

Can be caused by poor compatibility between rootstock and scion wood. Will always be a comparable weak spot. Al

There are very few commercial sources which use anything except a bud graft, to the best of my knowledge. If it is a bud then I think Al's explanation is the likelier. But I've experienced the same thing Macmanmatty2 describes when I've done a whip and tongue graft and pushed the pieces together too hard.

There are very few commercial sources which use anything except a bud graft, to the best of my knowledge. If it is a bud then I think Al's explanation is the likelier. But I've experienced the same thing Macmanmatty2 describes when I've done a whip and tongue graft and pushed the pieces together too hard.

I just re-read Al's post (incompatibility between rootstock and scion) and remembered grafting Flemish Beauty pear to a Bartlett I bought at a nursery. No idea what the rootstock under the Bartlett was. The FB overgrew the Bartlett, and it does bulge some where I made the graft.

But the tree is a weed. We just can't keep it back!

Good luck,

M

I ordered a Yarlington Mill on B9 from Cummings and planted it 2 years ago, boy is there a bulge at the union! Now who would have known those 2 were incompatible? If I ever get off my can and take a pic. I'll post it. Maybe a round of chemo. or 2 would save it.

M9 always has a big bulge as often does M26. Not observed any correlation to weakness and I manage trees from 1 to over 100 years old that have large bulges at graft unions. We don't get severe winds, however and I rarely lose a tree by spltting at graft. Last time it happened it was the Cornell G30 and a Kidd's Orange Red from Cummins. It had grown beautifully for 5 or 6 years then snapped. Windy site.

Good to hear about wind being an issue with that graft H-man, glad mine will be a dwarf being I'm out here on the plains of KS. The wind tipped one of my 6 - 5th leaf trees about 10 degrees the other day. Guess that tree will be staked (again) for a few more years.

What I have done in a case like this has helped is to cut the bark vertical about 2 to 3 inch long on the root stock, [smaller side]. about 1/2" apart.
These cuts will expend and grow larger in diameter, you might have to repeat for two or 3 season's.

FWIW: a shot of the graft union on my Yarlington Mill on B9. Methinks Cummins musta put a golf ball in there.

{{gwi:122117}}

I wouldn't worry about that at all.

What is the tissue that grows as a result of an incompatibility? Do the xylem and phloem tissue remain organized normally with callus tissue forming to the outside?

On M26 and M9 I believe the issue is not the result of incompatibility and a resultant weak graft union. I think it is merely a concentration of carbohydrates with no useful place to go. The union may actually be stronger as a result as I suspect that that bulge contains a lot of phenols and other wound protecting chemicals. This is just leap of logic, not based on info I've read that is scientifically verified. You could call it BS but I'd like to think of it as educated BS. Maybe someone else has an answer based on actual research.

The failed graft union I mentioned earlier had no unusual bulge and looked normal.

Incompatible stock

Repair

I have a 15 year old apple tree that looks like it has an apple hidden inside that graft union. It regularly bears a lot of apples each season. I wouldn't worry about it all.

I wouldn't either...I've never seen extreme differences in apples... you should be fine with a slight bulge.

Picture would be welcome.

These are 2 apple trees from my yard. First is a queen cox on M27 and the second is a Chehalis also on M27. Both are around 15 years old and bear heavily. I suspect the M27 rootstock causes these huge bulges. They've gotten bigger over the years. My newer apples are on Geneva, M118 and M26 rootstocks. They look a lot better.

Oh wow...thanks for sharing!