Nebari improvement technique

In this video, I'm trying to improve nebari on Fiels Maple / Acer campestre. One side is missing any significant roots, making the tree base unbalanced. The original plan was to approach graft seedlings with roots this spring. Due to time constraints, the plan failed.

After seeing Dan Barton's video    • Improving root ramification on bonsai  
he uses a technique with drilled holes soaked with rooting hormone and filled with matches I decided to try it on my tree. As Dan said in this video he saw the technique mentioned in the book by Deborah R. Koreshoff.

Here is what it looked like during a sweltering July afternoon at 35°C outside.