LanceMac10
Imperial Masterpiece
But you definitely seen substrate in the middle of the root mess. So...fine roots to feed have to be below.

If you keep moss where you have it, I wouldn't see too many problems. If you start trying to remove the "substrate" from within the exposed roots, I think you might run into trouble. There are roots in there, active roots I'm sure. If you repot next spring you can actually see just what kind of roots are in the container.
Apologies if it seems I'm bashing your tree, I'm just offering my thoughts. I wouldn't waste my time if I wasn't concerned with seeing you succeed. I got to wait on @WeeMac like a servant!!









That root over rock of mine died a couple years ago. That one still hurts. Not a great tree, but I had it for awhile. I'm 0-3 with Tridents.










Enjoy!!!



