Growing Trees in Loose Rock

(I think this is in the right section)

Cody of the Cody'sLab Youtube channel does lots of things with growies and non-growies.  Much of what he does is based on things he wants to try and observation/revision.  I will note, that he also plays with toxic gick too, especially mercury.  At least I can play with mercury via his exposure?

Way back in May 2017 (this year - yes my playlist is enormous) he showed himself and his dad out on their property planting store-bought starter trees amongst the trees already established in a rocky part of the hill behind the house.  While I take several objections to his approach, the concept is quite sound, especially since trees have already established themselves in that dry, high, arid land.

Objections:
Store bought trees rather than seed (especially because the root-balls were TINY)
adding water crystals to already water-retentive soil
and of course, not taking it far enough.  Where are the water-retention features on that enormous hill?  For example, there are no horseshoe berms or thoughts to take rocks and establish trees all along the hill...

Interesting. Even under those rocks there is good soil to access.

Personally I have no problem using something like those aqua crystals for a one-off planting of a tree.  They are biodegradable, and over the life time of the tree are of negligible significance, but they can potentially make a big difference to getting a tree established.

Under the rocks is exactly where I would expect to find great soil.  It collects organic debris such as leaves and sticks, plus holds the material that was in the air before the trees (in this case) slowed the winds.  Rocks also allow air flow, so oxygen and carbon dioxide can readily exchange, and most importantly, rocks in contact with the ground that are sheltered from sunlight and high winds will precipitate water from the air pretty much year round.

Air, nutrients, water. done.

I only object to water crystals because they are redundant, though I understand it as a kind of tree insurance and not toxic.