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Acer buergerianum


Restyling a Problem Japanese Black Pine

by Andy Rutledge, U.S.A.
Photos by Howard Smith, MD & Sylvia Smith, U.S.A.
The raw material: a tall, ugly black pine

Not all bonsai material is ideal bonsai material. In fact, most of the trees we enthusiasts get to work with have significant flaws and present difficult compositional challenges. In these cases we simply have to make the best of what we do have.

This Pinus thunbergii (Japanese black pine) has several flaws and it is clear that it will not be a very successful bonsai in this design. Let’s see what can be done.

Right: The current front.


Significant Flaws: (image below)

1. Surface root structure is very poor, especially from this angle.
2. The first branch is probably too low and too strong for the current form and for such a thin trunk.
3. The first two left-hand branches are stacked one upon the other.
4. There is no branch at the first major turn in the trunk. This makes too wide a gap between the first and second right-hand branches.
5. The second and third right-hand branches are stacked one upon the other.
6. The trunk is too thin and weak to support such a wide canopy. The current form is inappropriate.

Here are the most pressing problems with this tree


the front and left sides of the tree


the back and right sides of the tree

As you can see in the images above, none of the four basic sides will present any chance for great improvement. We have to look elsewhere for a better front. Let's first start with the surface roots and see if any side presents a possibility.

the front rootage

This is a poor angle on the already poor surface root structure. Ideally, the rootage should radiate around the entire circumference of the trunk. Sadly, this is not the case.

the back rootage

This is the worst angle on the roots. The back side of the trunk turns under like a heel. No surface roots are to be found.

the right-front quarter

Right front quarter:
This presents perhaps the best angle on the trunk for the surface roots.

Now, let's see what kind of trunk line this angle presents for the tree...

the new front for this pine

This is the front (image right) that holds the most promise for the visible root structure.

The trunk line from this angle is not bad, but there are still problem areas, most notably the absence of a branch at the first turn halfway up the trunk. However, if we consider a bunjin (literati) form, there are definite possibilities.

If we remove the lowest branch, converting it to jin, and address the volume of the upper branches, perhaps we can create a more elegant form.





The new design

Here (the sketch below) is the proposed new design for this pine. We can see immediately that the trunk is put to better use and the branch structure is much more appealing and more natural looking.

Note the addition of an element - a jin at the first bend on the right. This will have to be added; inserted into the trunk in order to fill the conspicuous void.

the proposed new design

Oddly enough, this design has the first branch on the back(!). This is not ideal, of course, but the back branch softens the form and fills what would otherwise be an uncomfortable gap between the soil and the primary branch (on the left).

remove foliage from the lowest branch

First, we get rid of the foliage on the lowest branch in preparation for turning it into jin.

step 2

All foliage gone. The back, horizontal branch is long dead. Only the front portions were alive.

step 3

Crush the bark with pliers to loosen the bark for easy removal.

step 4

Begin peeling the bark.

step 5

Be sure to cut into the bark all the way around the branch where it joins the trunk so that you won't peel the bark into the trunk.

step 6

Use a small grinding tool to shape the portion of the jin that was already dead. The new jin can be carved with hand tools, but should be left to dry for a season before carving with power tools or a grinder..

removing extraneous foliage

Now the branches need to be reduced a bit to bring the profile in toward the trunk just a bit. Remove outer shoots, leaving the inner ones to form the desired profile.

Wiring the tree

Here, the author (left) and Howard (right) wire the entire tree. You can use annealed copper wire or anodized aluminum wire.

wiring the tree

In this case, copper wire is used because this is an old tree and many of the branches are very stiff. If we use aluminum, we will have to use relatively thick wire to get the desired holding strength.

repositioning branches

Above: Repositioning the branches.

lower branches finished

Here (above), the tree is wired and the lower branches have been repositioned

inspecting the work so far

Image above: Inspecting the position of the branches. The apex is not correct; too far to the left.

correcting the apex

The apex (image above) needs to be place more to the right in order for it to occupy the best position

Adding a jin

adding a jin

We need to address the conspicuous void at the first major turn in the trunk. Since we cannot grow a new branch there and grafting a new shoot would result in a comparatively juvenile branch even after several years, we have to do something else.

We have prepared a jin to insert into the trunk to appear as if it were a long dead branch that had always been there.



An appropriately sized bit is used to drill a hole for the jin peg (image above). After drilling the hole and confirming that it is of the right size and depth, a depression is carved into the trunk that will accommodate a shallow portion of the jin circumference. This way, when the jin is affixed to the trunk, the end of the jin will be inside the outer bark and cambium. This will allow the wound to heal up to and around the new jin, creating a natural look.

the new jin

The jin has been carved on one end, leaving a peg that we can insert into the trunk.

The results

the final result

The final result of the work (image right). You may notice that the lower left jin has been reduced. This had to be done to prevent it from clashing too much will the first, back branch.

The overall form is much more elegant that before and the branches and trunk and roots are all used to better effect.

This work was done in the fall season, so more needles than normal were left on the branches. Provided that the buds are forming well, more needles will be removed in late winter or very early spring.

Some problems

There are still some aesthetics issues left to be addressed:

  • The lowest jin on the right has an odd angle that will have to be addressed, either with carving or significant reduction.
  • The primary branch (mid-left branch) has a poor angle off of the trunk. It was not moved very much because it is quite old and impossible to bend without significant damage. It will either have to be broken or slightly disguised in the future.
  • The width of the right side of the canopy will have to be reduced in coming years as interior buds take over for the current exterior ones.
back branch removed - bad

Above: Virtual image with the back branch removed.

Notice how the tree would lose balance and become less natural looking if the first, back branch were removed. Here, the space between the soil and the primary branch is too great and too severe. This images makes clear just how important the back branch is to the design.

a suitable pot (virtual)

Here is a virtual image of the tree in a somewhat appropriate pot. It is already a fair approximation of the proposed design sketch. In time and with refinement, it could make for a decent bonsai.