But of course the roots of any real tree act in both capacities. On the side away from the lean, they grip the soil and provide stability through tension; below the lean, the roots serve as a rigid base to support the trunk and canopy. Which, then, should the artist choose?
Interesting article Carl and I agree with the above statement. However, bonsai being a visual art, the overall effect and visual flow of the tree must be taken into consideration when deciding such matters.
Let's take a cascade for example, of course there are roots around all sides of the trunk, but due to the extreme tilt of the tree only the roots on the opposite side of the lean can be seen grasping desperately at the ground. The roots on a cascade tell part of the story, without them the tree would indeed appear off balance.
At what point between the cascade and the slanting style is it okay for the roots to flip back around to the lean side. At what point would it be visually acceptable?
The tree above bothers my eyes as they traverse down the trunk and then abruptly change direction and to my eyes, an unnatural one. The roots on the opposite of the lean seem to be missing; there is emptiness, a void, a space that cries to be filled there. Although I think a strategically placed rock on that side would solve the problem, roots would solve it better.
Some may argue that you must work with what the material offers and I agree to a point, however, we also must correct what faults that we can. Most root faults can be corrected with time and should be instead of defending them.