In The Natural Way of Farming, Fukuoka mentions that he did prune his appletrees (and others, but the apples needed special attention). He doesn't specifically mention anything about how he pruned them, however. Do you (Larry or anyone else) have experience with how he strengthened the branches and improved yield?
I just wrote about this in another reply. I don't recall seeing Fukuoka-san prune his apple trees. In general, people prune trees so they will be easier to harvest. With apples and some other fruit trees, the fruit sometimes becomes too heavy for the branch and it breaks off. This is partly due to the long history of breeding. For his citrus trees, which were is main cash crop, he thinned the fruit in early summer to avoid this and so the ones that were left would grow to a good size. Anyone else want to add something to this?
onestrawrevolution.com There is no time in modern agriculture for a farmer to write poetry or compose a song -- Masanobu Fukuoka
Breeding no doubt is a big factor. Grafting onto rootstock doesn't help either.
I don't think he ever mentioned thinning his crop in his books, although I distinctly remember him mentioning that thinning spreads disease in the orchard if you leave the undeveloped fruit on the ground.
I think when I plant my own fruit trees they will all be from seed, damn the consequences. At least then I might find the genetics to make healthy trees.
Fukuoka says quite a bit about how he prunes in Natural Way of Farming. I have the pdf version so I'm referencing those pages.
3. Fruit Trees (pg 159)
The Argument Against Pruning (pg 172)
The primary discussion is that pruning should only be done to encourage the natural form of the tree, the form in which branches do not cross haphazardly but are evenly spaced, and there is a main leader growing straight up. He goes into detail that exactly what the "natural form" is has been forgotten over time due to scientific pruning strategies, so we do not even know exactly what a natural fruit tree should look like. In general, a central leader (vigorous, upright leader) with an overall conical or triangular shape is the correct natural form. The tree should only be "trained" to the natural form for the first 5-6 years, after which the need diminishes. The tree is trained to the natural form by nipping off unnatural buds.
A tree will naturally create a form where each leaf receives sunlight, branches do not cross, and air can circulate. A tree would not naturally tangle itself up and create conditions for disease, or trees would not have survived for so long before humans came along. If the tree is pruned irresponsibly, the tree creates many buds at the cut point which then create an unnatural situation.
It is a similar argument as those against tilling, weeding, pesticides, and fertilizing. By performing these actions, man is only creating more work for himself later on, leading to endless toil. A tree improperly pruned, must always be pruned and tended to. Soil tilled, must continue to be tilled to break up compaction. Pesticides destroy the food web balance, inviting more vigorous pests. Ect...
I also found that, as far as branches breaking goes, there's not really much you can do about it. Whether the tree makes strong branches or not depends mainly on genetics, which are often poor in domesticated fruit trees.
Nice point about the solution creating more of the problem.
One factor I remember from an organic orchard grower in NZ was the angle of the branches. He said V-forks split easier under heavy weight than a blunt-angled branch. So they'd select for, and train to, a wider-open crotch or near-horizontal branches, with or without a central trunk. The shape they were trying to avoid was a narrowly split trunk. This seems to agree with the sketches, where competing or crossing branches make the tree more vulnerable. The NZ orchard tree shapes did look more natural than the ones I've seen around here lately, though still obviously pruned. We used tall ladders to get to the upper fruit, and they were strong enough you could also climb in them if you liked to pick that way.
Some nut-trees do well as a coppiced stand of shoots. I wonder if any of our fruit varieties thrive this way? I suppose the graft would be way down low and subject to infection, unless you lucked into a root stock with tasty fruit.