Sometimes they seems to do best all on their own...
I swung past my favorite local feral tree today looking for a few bushels as base for some sweet cider.
It's one of those trees that has never seen any care and yet is near perfectly formed, shows no sign of scab or other fungal issues and drops tons of fantastic and clean fruit (every other year).
It always strikes me how I can fuss over my own trees, pruning spreading branches, spraying all season, thinning, etc......
And yet here is a tree that consistently produces fruit as clean, well sized, and colored as anything I get off my own.
I understand some of it. It has a wonderful location all alone out in the middle of field, good soils, great sun exposure, and lots of air movement.
Clearly it is near scab immune as I have never seen any on it..
..but what about the bugs? Why does it get so little damage? Although it is all alone from a growth standpoint, there are other ferals within thirty yards...the whole valley is full of them. Bear and deer do scour the drops at this tree always (they like this variety too!)
I see this here and there, and I am sure some component of it is gentic, but grafts from trees like this rarely perform quite as well. Being on their own roots could be part of the equation, and I think microclimate plays in as well. Sometimes it makes me think there are some pieces of the puzzle we just are not getting.