I’m just curious how much varieties matter in situations like this. Goldrush is infamous for runting out from early fruiting if you aren’t careful, so might those characteristics help in this situation? Could it go fruitful quickly, particularly if you summer prune and maybe pull down branches, then it wouldn’t be as vigorous on top so the bottom could still get what it needs? Or does the fruiting draw even more of the energy?
I have no insight on this, but was just curious if the locations of the two varieties might be more likely to work than with other varieties.
@zendog Yes good point- one reason I put Goldrush up top, plus only moderate vigor. Guess I could leave as is for a year and watch growth rate of top vs bottom tier although strong apical dominance might take a few years to show. I can summer prune at or above 90 degrees when fire blight is inactive. Hmmmm.
Like @northwoodswis4 mentioned, gradual sun exposure is the key. In the past, I did not think about this when I pruned my trees esp. peach trees and my cherry trees. One peach and one cherry got sun scald quite badly. Lesson learned.
These days, I white wash my trees, the ones that I pruned to open-center.
If topworked only a few tree’s. And i have less sun intensity than most people in the states.
But if never whitewashed small branches for fear of sunburn. It seems mother nature has build thinner/younger branches to resist intense sun. Logical if you think about it. In nature new/young branches experiance mor changes. While older branches verry much experiance the same light intensity etc over the years.
Another lightbulb: try not to graft vigorous and non-vigorous varieties on same tree or will be hard to balance growth.
Two Schools on Balancing Vig and Non-Vig Branches:
Mr. Spellman from Dave Wilson says to balance growth by heading the vigorous variety and not touching the non-vigorous variety.
I think it was Mrs. Ralph who wrote Grow A Small Fruit Tree who advised the opposite- said heading a jumbo branch just invites a super vigorous response, best left unpruned but do head back the non-vigorous branch to stimulate vigorous response.
if it’s a central leader tree. I know some-one who then grafts low vigor variety to the central leader. Since that is the most vigerous part. Seems to work great.
For a vase model i would not graft vastly different vigor scions. Or not unles i tend to keep them balanced “myself”.
You can also summer prune (lorette) the overly vigerous branches. Switching them from growth to fruiting is a good way to lower vigerous growth.
And ofcourse bend them horizontal if you want to lower vigerous growth. Bend them more vertical if you want to increase it.
Increasing vigor on lower vigor branches can also be done with lengthwise cuts. If only done it twice. But they healed up nice and i think they worked. (lengtesnede is what we call it here)
You cut a line with your grafting knife lengtwise on the lower vigor branch. The callous that heals that line then becomes vascular and increases sapflow to the lower vigor branch. Or at least thats the theory i was told.
A good espalier book, has chapters on all the ways to balance growth of different braches. I think all these techniques will be useful to on a “frankentree” with different vigor varieties.
I could not find an english source. And the webpage is shorter then whats discussed in the book i have. But to give you an idea.
The pruning rules of Vöchting and those of Koopman https://fruitpluktuin.nl/fruit/Snoeien/snoeiregels http://www.hoogstamboomgaard.be/snoeiregels.html
Use the google translate plugin.
These are empirical “rules” that have literaly been around for a century or more.
If you want to look for the underlying principle/theory
Plant Physiology is the scientiofic field that does that. You can read for days (done that) or years about it there.
This article goes over some of it
Goldrush will not likely starve out lower grafts if they are more vigorous growers and most varieties are. If the top is shading lower wood just summer prune it.
Brutal technique you use, but a common one. As long as light hits the developing grafts they should respond with growth. For folks that want to keep getting apples and keep the tree beautiful, I recommend using my usual method.
My experience is almost entirely with water sprouts coming off of the trunk or existing scaffolds nowadays. You keep them growing straight up for a couple of years and they tend to grow with vigor and existing scaffolds are perfect for pulling them to a more horizontal position just before they become too stiff to bend- when I miss that time I cut a hinge. The sooner you bend it the less vigorous the growth. Gradually you remove the scaffold that you tie your graft to and in 2 or 3 years after grafting you may eliminate the original scaffold without butchering the tree.
About 25 years ago I cut down a tree whose apples I didn’t like and it became my first grafting experience. I didn’t get around to removing the trunk and the next season it sent out very vigorous water sprouts which I grafted onto the following year. I’ve never had grafts grow as quickly since.
Incidentally, I’ve often posted here of the advantage of using more vigorous varieties on the lower tier of trees and less vigorous as you graft above. This approach will create a much more manageable multi-variety tree over the years if you are training it to a central leader 2 or 3 tier tree.
That leaves just one tree am not sure about: top and bottom tiers both Keepsake, a moderate vigor variety. Maybe summer pruning the top tier is all that’s needed? Or there’s still time to re-graft the top to Goldrush or even eliminate the leader just above the bottom tier. What do you think?
Agree your makeover method is probably a wiser path but I hadn’t planned ahead for the makeovers- kept holding out hope the Black Limbertwig taste would improve. Then love at first bite of Keepsake (not pretty but fabulous taste, a Burford “sleeper”) so at 75 I wanted a fast makeover hence the brutal route.
That’s funny, I removed Black Limbertwig the first season I tasted it. Nothing improves that much with time or varies that much between seasons. It was bland on bland.
As far as your question, I don’t think it matters a great deal what you decide to do now except having more grafts could mean more apples sooner of that variety. The question of running with an open center or central leader, much the same.
A central leader is a bit more efficient at converting light to fruit but is more complicated to maintain than an open center. For a commercial grower surviving on narrow margins it is a different equation than for a home grower.