Multigraft and apical dominance

I searched around maybe i missed it i have a question about multigraft apical dominance.
Does the tree recognize a cardinal central leader or does each scion recognize an individual leader?

Each tree recognizes where you graft the scion. If not grafting on the central leader it’s best/beneficial to graft on a branch with strong vigor and heading upright.

Your goal is scion vigor always when top working a tree.

Dax

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Great topic. I was going to post the same question.
So, in theory, the least vigorous cultivars should be grafted upper and most vigorous cultivars should be grafted lower??

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apical the key word & is why you graft on ascending and upward branches for the greatest growth.

vigor will be highly reduced, otherwise. But if you were to graft on branches going sideways instead of up they will I’ll assume gain upward growth if there is plenty of sun for them (to find a path to go up.)

So, I graft the most vigorous and the least vigorous in an apical dominant position where it has plenty of sunlight. Now understory trees trees such as pawpaw that may not see much sunlight, it’s best to graft them as low as possible for increased vigor. My rule of thumb is anywhere from a few inches above the soil line to 10" up. If you are able to put a 3-flap or bark graft 10" up you’re going to see extremely good vigor. If a less caliper seedling and you’re more or less matching scion diameter to rootstock, then a cleft or a whip & tongue or a V-cut all will yield similar results… as well as bud grafts, i.e. chips or T-buds or Greenwood budding with leaf attached as being examples. There are ring grafts, too. There are a lot of single bud grafting techniques to use just as well as sticking a scion into a rootstock.

Attaining vigor.

Dax

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I don’t understand the question- what is a cardinal central leader?.

Apical dominance of the trunk is usually only lost if the diameter of a scaffold exceeds or equals the trunk itself where the scaffold starts. If a scion is much more vigorous than the variety it is grafted to then the branch it’s grafted to will probably require special attention through summer pruning to keep it from eventually dominating. Probably best to graft such wood to north-facing branches.

As far as the idea of less vigorous varieties being grafted higher- that’s been my approach for years. I sell a lot of dual variety apples and made the mistake early on of not considering relative vigor of varieties- a more vigorous one on top tends to stunt the lower tier. These trees are constructed of a lower tier of the original variety and then any subsequent tiers of a different one- the second variety starts as a new trunk above the first tier.

Equal vigor between tiers is ok, but it is a real plus to have a less vigorous one above. Such trees are the easiest to manage as central leader, christmas tree shaped trees.

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Beautiful explanation.

Dax

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Just to clarify my jumble. I was looking and thinking of each graft as its own ‘tree’ it has a main branch which grows out with the smaller branchings. So does the main branch of each individual graft get read by that scion as its ‘leader’ or does the largest and most vigorous graft section get read by the whole tree (via trunk?) as a leader (what i was thinking as ‘cardinal leader’).

I aim to grow out each scaffold as a central leader shape within itself. In a single scion tree i think this just keeps shaping and light in balance. But with multigraft growing each scion like its own central leader shape … thats where i got to wondering who is dominant.

Its bc i have a pre made multi-graft tgat i got back when (doh). Golden Delicious is a beast and tho i do balance the grafts is is clearly larger.

So as you said about scaffold thickness - With GD being so thick that must mess up where the auxins report to.

Alan TBH i really hate my brain sometimes. Lol.
Thanks for the input, truly appreciated

Ok. Ty Dax. So relative position will affect vigor.
The tree i have is a premade one i got as a gift before i started with bare roots and reading a lot if info. With yr info i see why i wrestle with it so much bc they put GD highest on the trunk and its waaaaaay more vigorous than the other scions. Dammit.

I think these were all Tbud grafts but im not sure bc i am just not a grafter yet. Not all that into it i like single scion trees

This tree may end up as just a GD if the balancing is too much of a PIA.

It depends upon the shape of the tree. You could have a tree w/o a central leader and the insides of the entire tree opened up for scaffolds on the sides that may play the role as multiple ‘leaders’ that perform with very high vigor. And furthermore as Alan touched on, the vigor of the scion will be influenced “as a whole.” So (I don’t know) let’s say that Golden Delicious has more vigor than Winesap. Well if you place a scion of each on a scaffolding ‘leader’ then of course the Golden Delicious will grow more… as I think you understand already.

To your questions for me, maybe if they had put another variety on the central and dominant leader then the other varieties or variety i.e. Golden Delicious may have less vigor because it was put on a less dominant shoot.

It’s all relative as Alan pointed out and I pointed out. Placement on the tree and vigor of both scion and rootstock all come together on how the tree grows and/or what it becomes.

Hope this helps.

Dax

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!Yes - thats what i was trying to get too (while getting myself all tangled up)

I think i will change mgmt of that tree with that in mind. And i love this whole discussion bc auxin management is fascinating in itself when u add multigrafting in even more so.

Ty :sunglasses:

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where can I find Info about which common fruits tree cultivars is vigor than others,or listed in certain order?

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I use Orange Pippin as a resource. In trying to decide which scion might do well with what stock.
Iam sure i spend far too much time doing this :joy:

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Books on apple cultivars; books on pear cultivars; etc.

I have two pear books where within one of the two describe vigor.

Otherwise I’m sure many growers supply that information pertaining to each cultivar they sell. 10-year growth rates for example. Of course (for everyone reading) rootstock influence will be a player.

Dax

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A lot of newer cultivars aren’t listed in the book, or only partially list

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I have a multigrafted A.pear tree, that I bought from nursary, at least on its 8th leaf. One branch doesn’t grew, instead get shorter and smaller. This year I didn’t let the tree set fruits and fertilize it from spring on. The cultivar on upper position grew at least 2` but the cultivar in lower position didn’t grew at all just few new leafs. I was hoping it grew few inches so I can take scion wood and graft it into other pear tree

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Nature’s a funny animal isn’t it?

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Golden Delicious, at least all the sports of it I’ve worked with, is not a highly vigorous variety, so either your tree is mislabeled or it has something to do with the original graft being done in vertical position compared to the other varieties in the tree. Or the other varieties are especially spurry and precocious.

I like your idea of treating each scaffold as an individual central leader tree- even before you mentioned it here- it’s in the pruning guidelines I’ve posted on this forum (in guides section). Keeping secondary branches subdominant by removing excessively thick ones is one of the main methods I use for deciding how to adequately open up trees to light- that’s the first wood I remove.

I still don’t understand your question about individual dominance of scaffolds over the central leader in relation to the developing scion.

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Reg,
Two of my first apple trees werea Honey Crisp on an unknown rootstock and a 3 in 1 of Golden Delicious, Summerred and Melrose. As a beginner’s luck ( that I did not have), HC took 6 years to flowers and went biennial a couple more times.

For the 3 in 1, GD took over. I did not know anything about pruning. The tree was leaning. A freak snow storm in late Oct brought the tree down ( heavy snow on a tree full of leaves). That’s the end of my 3i in 1. GD did take over, like big time.

@alan, I did not believe the tree was mislabeled. I bought it potted from a reputable local nursery. It produced fruit for a couple of years. It was GD.

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I have my opinions based on my experience- but I’m far from infallible. However, GD is not generally considered an especially vigorous tree. Here is a fairly exhaustive list- that is in the number of varieties they rate. They only base vigor on 3 levels in which YD is rated in the middle.

http://www.homeorchardsociety.org/growfruit/apples/estimated-tree-vigor-for-apple-varieties/

Also a commercial growers guide from a download from Starks has apples rated with 5 levels and the YD varieties they list both fall in 3 from a possible 1-5.

It amazes me how little info there is to be found about relative vigor of cultivars in the form of charts or grafts. So much is available about rootstocks, but there is great difference in vigor between varieties that is also important info- especially for commercial growers trying to determine the perfect spacing for max productivity.

My experience with Melrose is that it is equally vigorous as YD. Honeycrisp is well known for being a particularly weak grower.

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Yes Mamuang this GD is a relative monster too.
Funny we both started with multigrafts. Lol. Harder to manage not easier