Trunk Chopping Potensai...
Written by Brian Inglis, Queensland, Australia
Trunk chopping has a twofold purpose. First to reduce
the height of the tree and secondly to induce taper into
the trunk. I have developed an improvement on the usual
method in the case of the formal upright style. It should
be remembered that the formal upright style requires that
the tree has a perfectly straight trunk and the usual
technique is not conducive to this especially if the
trunk is chopped a number of times.
Note that with the standard method, the trunk is cut
and tapered to a branch which is then wired up to become
the new leader as shown here. This will always result in a
bump in the trunk where the
new leader starts because it is the branch that is bent.
Technically this means that bonsai is not in the formal
upright style.
I take it a step further.
The branch on the right is destined to become the new
trunk of the tree.
Instead of bending the branch
up, I make an exaggerated deep concave cut into the trunk
below the branch and bend the trunk! This serves to position
the new leader directly above the centre of the trunk below
it, thus maintaining the integrity of the formal upright style.
When healing is complete, the trunk is perfectly straight
and excellent taper is achieved.