Distance beetween fruit trees on a small lot

[StillHope]

Does anyone have a small lot (8000sf ft) with already mature trees on not far from each other?
I am wondering what is the smallest distance (7-8 feet?)between the trees that can allow them to produce more or less normal?

Any examples of what type of healthy trees you have within relatively small distance from each other ? Thank you in advance.

Note: I realize that it depends on a particular tree root system.
But hoping to hear some success stories.(Or the opposite).


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