A year's progress with a field maple root over rock bonsai

 

Acer campestre on carboniferous limestone in a Peter Krebs pot. Last year I posted an image of this project for the first time here. At first glance it's hard to see what has been achieved in the interim, but comparing back to the start of the growing season, there's been some progress.

Sacrifice branches, grown solely for the purposes of promoting vascular growth below them, were promoted across lower half of the canopy. Moderate to heavy fertilisation allowed the tree to grow out some long sacrifice branches and heal some trunk scars from previous branch removal. I removed all the sacrifice branches as, at this stage, I want any scars to be relatively small.

As you can see there has been some significant thickening and minor taper improvement of the main trunk and left sub-trunk, the right sub trunk is being kept quite slender. 

Next year I'll focus on growing more useable branch structure with reasonable internode lengths, with fewer sacrifice branches, and in 2022 I'll decide where I need selective thickening again. Meanwhile I'll keep pinching back the apices to keep taper.