One ring if netafim around tree enough?

Pine starts with ...
I'm installing netafim around all my fruit trees and would like to know how much line to place around the tree.

Is one line right around the drip line of the tree enough no matter how large the tree is or do bigger trees need more than one line around the tree spaced 300mm apart in or out from drip line?

I've seen photos of people's drip lines coiled from close to trunk all the way out to the drip line.

Also how do I work out how long to run the system for each time? I guess it all depends how deep the root system is, the netafim I bought emmits 1.6L/hr.

How deep are the roots on peach, nectarine, apricot, plum and apple trees? Do they need longer deep waterings or are their roots close to surface and only need shorter watering times?