There is a great story in Book 5 of the Ringing Cedars series describing how groves of old apple trees on a couple of abandoned estates in Russia produce more apples than the local "village orchards which are tended to and fertilised."
These older trees, "dripping with fruit," showed no signs of worm infestation or insects, even though they were not being sprayed with pesticides or chemicals as the trees in the local villages were.
When a great frost hit the area in 1976, the local orchards were destroyed and new trees had to be planted. The old apple trees, uncared for by man, were unaffected by the cold "and not a single tree was lost." Oak trees and Siberian Cedars surrounded these old apple orchards, providing protection from the elements and sharing their light energy as well.
It occurred to my wife and I that we (mankind) tend to overemphasize our gardening techniques and we all might be better off if we focused more on simply being planters, rather than being gardeners. A property which has been thoughtfully planted with a variety of growing things that can support one another seems quite able to flourish on its own and requires little additional help from gardening to survive.