[Superman]

The second pic looks north.

You have a nice spread there, SM. Outdoor fireplace!

Given the principle of keeping the area around the trees wet, I wonder if basically two hoses can be installed in a Figure 8. That way, there is drip line on all four sides of each tree.

I am skeptical but respectful of the assertion that the drip rate along a LONG run of hose might be virtually the same everywhere. When I have daisy-chained ordinary flat soaker hose, the last section delivers little water. But....that system is basically low-pressure. If the system you are advising is higher pressure, then it can serve a larger area.

BTW, I am not terribly worried about cost. These systems are certainly not expensive. I want effectiveness.