Patrick Mann

S Bengi wrote:The roots normally produce the growth/master hormone for the top part of the tree thus inducing earlier fruiting and dwarfing.  

I always understood that a weak root system was responsible for dwarfing. Can you share some more info rmation about growth inhibiting factors from the root stock?

That's definitely a graft at the bottom.
Since you are already bending branches, I would use that to manage different vigor of varieties. Bend to a lower angle to retard, less to encourage growth.
That said, you might want to avoid going below horizontal. You are likely to get strong watersprout response close to the trunk otherwise.

I noticed a couple of statements about cross-pollination that are not accurate:
* an orchard of purely Ark Black would produce seeds that grow Ark Black due to lack of cross-pollination
* grocery store apple seeds would not grow true due to cross-pollination

Very few apples are self-fertile, so you're almost always dealing with cross-pollination. Those Ark Black trees most likely get pollinated from other trees that could be miles away.
The seeds express different combinations of the genetic material on every pollination. I believe that includes self-fertile trees. So you always have a genetic lottery, though it's constrained by what's available in the genetic material of the parent trees.

Compost is good. But I would simply spread it broadly on the surface and not try to work it into the soil.

Here's a good discussion of roots:
https://hortnews.extension.iastate.edu/1992/4-1-1992/treeroot.html

In particular:
"There are many misconceptions about root growth in trees. Horizontal root spread is one of the more important. It is often said that the majority of feeder roots are concentrated at the dripline of the tree. Roots extend to that distance and much farther. Studies have shown root spread to be 4 to 7 times the dripline distance (radius) of the tree. This is an important fact to remember when applying herbicides, fertilizers, insecticides, and other soil treatments around trees. Careful consideration can prevent serious injury to your trees."

What do you mean by "trench composting"? Fruit trees have very shallow roots that extend well beyond the drip line. If you're digging a trench within that area you might end up cutting a large volume of roots.

I don't see anything wrong with these trees. Scab, tent caterpillars, beetles ... those are all environmental issues that can be fixed.

For scab: remove fallen leaves and fruit promptly from under the trees; or cover with compost. This will prevent spores from re-infecting. A grower here in the PNW recommends not mowing the grass understory in spring - high grass inhibits splashback and dispersal of spores.

http://scionexchange.us/ is a good resource

Afaik rust is spread by airborne spores. So treating the gloves won't help.
I've not been successful in preventing it. The better option might be to plant early varieties that are mature before the rust hits.

Pruning for light and air penetration is always good. I'm removing the worst branches and hoping for the best.
The best prevention is keeping the rain off it, but that's hard to do.