Hypatia Nachshon wrote:

Pls address my q. re; blocking ends of pipe.
I still can't visualize pouring a whole bunch of
water down the intake, and having it all gush
out at once.

No water gushes out the bottom, it's down in the ground, water will
slowly perk into the ground, and that's what you want for deep
watering... unless you have an underground spring directly below those
trees any excess water you add that the ground can't absorb will
evaporate at the surface, same as it does when over watering a lawn.
Were there an underground spring you wouldn't be asking about
watering, the ground would always be moist. If you're unsure do one
test pipe first to see how your ground perks, You can always place a
stopper into a pipe later, drop an empty steel can into the pipe, pop
a hole in it so it won't float, and you can always retrieve it with a
magnet. If your ground is very porous it won't matter how much you
water.