One of the main characteristics that we strive for in bonsai is that of a thick, fattened trunk. The bulkier we can make it, the better. A thicker trunk shows the proportions of a more mature tree. In nature, we know that the larger tree is usually the older one. And while trees may peak out in their height, or really slow down, they continue to grow sideways. I sometimes have the same situation.
But in a bonsai, it’s good, so we are always seeking ways to make the trunk look bigger. One notable method is to reduce the height of the crown through pruning. The shorter the tree is, the larger the trunk will appear in proportion. This usually works pretty well.
But we have lots of trees that seem to sit in the middle between thick and masculine, and those that are feminine and thin. Many of these trees are fairly unsuccessful because they haven’t really made up their minds on what they want to be. They lack anything that would make them distinctive. Do they want to be thick and powerful, like a Sumo wrestler, or slender and delicate like Geisha? So our job as a bonsai artist is to encourage the tree in one of those directions. Otherwise the tree becomes boring and lacks interesting qualities. How do you make those decisions?
Take a look at your tree and check to see how many changes in movement it makes. How many zigs and zags? If there is only one, or no significant change in direction of the trunk line before the point where you want to reduce the crown, it might be better to style it into a taller tree, introduce some curves in the trunk line, and let it mature into a tree with a slender, more subtle nature.
Here in the United States we tend to under value thinner trees. Often, these trees are classified as Bunjin. (Thin is not the only defining quality for a good bunjin) Now it might seem strange you coming from a person that admittedly likes large trees, but bonsai is still about proportions and making something beautiful. I very much enjoy creating bunjin style trees from appropriate material.
However, we must explore each piece of material on it’s own merits. We want to take whatever the tree has to offer and expand upon it. Sometimes that means cutting something back hard to a new leader and redeveloping. This can even be part of the original plan to growing a thicker trunk. Sometimes we have a great abundance of branches and many options to reduce the height with plenty of movement in the trunk.
There are times though, when the best solution is to use as much of the existing trunk as possible and lengthen the design. Pull a branch up and make it taller. A lodgepole pine is a great example of tree that would vary rarely make short, powerful tree. By nature, it is tall and slender and the option to grow it thicker just is not there.
As the trees get smaller, keeping a thin proportion becomes harder. If you look at most shohin, there are not many bunjin style trees. In fact, the trunk diameters approach or exceed the total height of the tree. They become sumo-like pyramids. The sense of delicate movement is much harder to express in a shorter tree. So next time you pick up a pair of concave cutter, think about what your tree has to offer, then feature those aspects, whether it be the trunk line, jin and shari, fruit, or whatever you might have.