Raw Material: Pines

Among the many email questions I get about bonsai are a few about Japanese Black Pine, Pinus thunbergii. Most people are completely lost about how to design a black pine, and rightfully so because it is so difficult. Pines are nothing like deciduous plants in their growth pattern and thus require their own techniques that are different from deciduous trees, and even other conifers such as junipers. The biggest problem with pines is they have strong nodal growth patterns. On pines, these nodes are easily identified as the whorls of branches. Growth between these nodes, or internodal growth, is difficult to obtain, and new bud breaks on older wood are nearly impossible. Some people recommend grafting as a cure for this problem, but I think this is an overly simplistic solution. Grafting has its place of course, but the real answer to grow pines using techniques that make use their odd growth pattern. That is what I will try to do here and in future posts about growing and designing pines. If you haven't already, you might want to read these two articles I have written about black pines on our website:

Black Pine Training

Black Pine Growing

I usually don't recommend black pines for beginners because the techiques are so sophisiticated from a physiological standpoint. In other words, you have to know a lot to even begin, and it is very easy to go wrong. Mistakes in black pine training are usually irreversible in the sense that you can very severely limit your options simply by making a few unfortunate pruning cuts. With pines you need a strategy that will carry you through to a design you see from the beginning, or at least maintain the maximum number of options for future design. I must admit that I don't design pines from the seedling stage, that is, I don't impose a design on them. I do the basic work and let the plant show me where the greatest potential is. I can do this because I have grown thousands of them, and I can predict pretty reliably how they will turn out. A beginner in the pine world doesn't have that kind of clarity because he doesn't have the experience. I hope to show you how to proceed with a few basic rules and concepts.

Bill D wrote me last week for suggestions in styling his black pine pictured below. He would like a 12 to 14 inch tall tree, but doesn't know how to proceed. This is your standard nursery grown Pinus thunbergii seedling. It has had little or no pruning to this point, and that's really good, because nothing important has been removed. This is the kind of plant offered by most nurseries and what you will find unless you obtain pretrained material from a bonsai grower.


As you can see, this tree doesn't resemble a black pine bonsai at all. It has a perfectly straight trunk with nearly no taper and a reverse internode space pattern (whorls get farther apart as you go up the tree). This is how pines grow, but it really doesn't matter because 90% of what you are seeing here won't even be in the final bonsai 'tree'. First, note and locate the nodes (whorls). Now notice, fortunately, that the very first whorl just above the pot rim is still intact. I say fortunately because, right now, these are the most important branches on the tree. Ironically, these are the ones that a beginner is most likely to cut off. Never remove low branches on a pine until you are absolutely sure you can't use them, they have done their job, or they are causing a problem. More on this later. Note that this node's branches are weak and small except for the one long one. This is not uncommon. Left to its own devices most trees would quickly wall off and shed these branches that were formed just after the seedling germinated, in the first season. You must do whatever you can to prevent that from happening.

This is my answer to Bill:

If you want a twelve inch tall JBP, that means you need at least a two inch caliper trunk, three inches would be better since most JBP are masculine and thus look better with a fatter trunk. So it looks like you have a long way to go yet. Here's what you should do:

Those few tiny low branches just a few inches from the soil: Keep all those, they are very important. They will be your sacrifice branches for fattening the trunk and getting some taper. None of the rest of the tree is usable as it is. You have a long straight internode to the first major whorl of branches that is about six inches or so up the trunk. There is nothing that will work for a first branch, so you will have to start completely from scratch. This is not unusual for JBP. Start by removing the entire top of the tree just above this whorl (the one about 6 to 9 inches high, at the white line in the photo below). You could have done it this summer, but it's too late now, so do it late this winter or early spring.

By removing the top you should get some bud breaks below this whorl, one of which would be the first branch or possibly the new trunk line. You could get a new trunk line out of the whorl by using one of those branches, but it is pretty high and the internode is pretty straight and uninteresting. so it would be better to use a lower branch from the internode for the new trunk line. So, you are doing two things here, one is to get the first branch, and the second is to get a new trunk line, one that would create movement and taper. If you can get these out of the internode section by cutting back to the top to the internode, then fine, you can leave some or all of the whorl branches as a sacrifices to thicken the lower trunk, but it would eventually come off after the trunk has reached the desirable caliper at the point just below the start of the new trunk line.

IF you don't get ANY new breaks below this whorl after pruning the top out, you are kinda screwed. You would have two options. One would be to grow a larger tree with the first branch and the new trunk line both from the existing whorl. The height of the tree would then be three times the distance from the soil to the first whorl, and the new caliper would be at least 1/6 this distance (remember the six to one ratio). Your second option would be to prune it even harder (an inch or two below the white line in the photo below). This would be done next summer, about the middle of your growing season. You would cut just below the first whorl and thus remove it. This will do one of two things. It will force growth in the internode, or the internode will die back to the first low branches you are keeping as sacrifices. Usually, if there are still needles in the internode, you will get a bud break. Even without needles you can still get it to break. If it dies back, you have to create the 'tree' out of one of the very first low branches. This will give you a broad base and strong turn at the bottom of the trunk which is not all bad, but it is starting completely over. You would then have the chance to make an even shorter and more dramatic 'tree'.

It's a little late to be telling you this now, but it would have been better to CUT the needles in half so I could see into the tree rather than plucking them. By removing them entirely you just reduced the chances of getting buds to break in the internode. This is the problem with pines, there is so much to know and you have to know it all at once to really come up with a plan.

No matter how you proceed, all you are doing at this stage is trying to get a first branch and a new trunk line. The entire rest of the tree will be created from the new trunk line. We don't need to deal with that now, but there is probably enough information in the pine articles to help you figure out how to do that. (End post)


I am going to expand my answer to Bill a bit by showing you the results of this kind of pruning on some other pines. The pine below could be Bill's pine in about five years. This pine didn't have a low weak whorl like Bill's, so obtaining a good low sacrifice wasn't possible. This tree was first pruned back to (1) on the photo below. This was the first node. This was done because the rest of the tree wasn't usable. I didn't get any low bud breaks after this chop, but I did get more bud breaks around the node (whorl). This accounts for most of the branches around area (1). One of the original branches at node (1) became the new leader, but the internode between (1) and (2) was still too long to be usable. So a subsequent second chop was made at (2). You can still see the scar. This resulted in internodal bud break as desired. The buds that broke formed branches (3), (4), and (5). Now we have something to work with.

The first branch can come from one of the small exisiting branches at area (1), probably one of the ones on the left. Note the distance to (1) from the soil line. The height of the 'tree' will be about three times this distance, or about twelve inches. The current caliper is about 1 1/2 inches, so it has to double for a finished trunk. Thus sacrifice branches will be necessary for at least several more years. The second branch should be less than the distance of the soil to the first branch. Branch (5) is a little too low and branch (3) is a little too high. Branch (4) is just about at the correct distance and on the right side of the tree. This would be my pick for the second branch and the start of the new trunk line. There is a branch and a new bud break in this area. The branch could be the new trunk line and the bud break could be the second branch. But this often doesn't work well. Usually it is better to use the smaller bud break and let it extend for a year or two. There is a node at its base, and when you prune back this new trunk line after it is stronger, you can get more breaks from this node and possibly a better selection for both the branch and the trunk line.

Now I would like to explain something complex that most people don't think about. At what point do you remove the trunk section above branch (4)? The section above branch (4) will be left as a sacrifice to thicken the trunk area just under branch (4). It should remain until the section under (4) begins to approach the desired final thickness of the finished tree. This is somewhat subjective, but we want taper to the top, so for a three inch caliper tree, the final caliper of this area should be no thicker than about 1 1/2 inches. If you let it get thicker than that you may lose taper from the last section and you will have too much taper going into the next trunk section. You also have to allow time for sufficient scar healing after the old trunk above (4) is removed. So you can see from the photo below, that it is almost already thick enough. In probably a year or two, the old trunk section will have to be removed, it's job completed.



The entire rest of the 'tree' will be grown out of the new trunk line created by branch (4). All of the low branches, except for the first branch, soon will have to be removed because they are already beginning to create a bulge or inverse taper at (1). What this tree is lacking is a good low sacrifice branch. The base trunk section is never going to be superb without one. Pines tend to come out of the ground like stovepipes and stay that way no matter how thick they get unless you can get a low sacrifice to induce taper. It's not too late for a bud break on the base trunk section, but as each year passes it becomes more difficult and more unlikely. The next best chance would be to repot this tree and really pump it up and then prune it really hard at the time that the chop is made above (4). This will often induce very low breaks even old healthy trees.

The next photo is an example of what Bill's tree might be like If he didn't get any bud breaks after pruning back to first whorl, and even after he pruned below the first whorl. This was a 'rescue' tree that I couldn't force back. Note that despite my massive pruning at (1), I didn't get a single bud break below this point. However, I do have a low sacrifice branch that I was using to correct the stovepipe nature of that straight taperless trunk. As it stands, this tree is utter worthless with its present trunk. This is a case where we will make a 'tree' out of the sacrifice branch and trash the entire rest of the tree. In a year or two, once the sacrifice is strong enough to stand on its own, I will trunk chop the main trunk at (4) and make the sacrifice the new trunk line. Now note that there is long internode in the sacrifice between (4) and (2). This is unusable. One of the tricks I do with sacrifice branches is that I work them as if they are 'trees' just in case a situation like this occurs, where the sacrifice becomes the 'tree'. I saw this one coming and pruned out the leader of the sacrifice at (2) last year because I didn't have anything to work with in this internode. It worked. I got a bud break at (3). After this little branch gets stronger and I force some secondary branching from it's base, I will remove all of the rest of the sacrifice above (3). This will make a tiny tree with the same caliper of the original tree, about three inches! There will be some major scar healing to accomplish, but this will be a massively tapered small tree with great movement.


This last photo is of another tree where I have done exactly the same procedure. You can see the results after a few more years. The old trunk was removed at (1) and the sacrifice was shortened at (2). So now the trunk line moves into the foliage. This last cut was recent so there isn't a definite next trunk section yet, but there is plenty to work with as you can see. Several more years are still needed for scar healing and more trunk formation and upper branches, but take note of the caliper and movement. This could make a nice little shohin of about eight inches with an almost three inch trunk caliper!


I hope you can see why working with black pines is so exciting for me, and why it is such a challenge. the last two trees are about fifteen years old with at least another five years to go, but they will be very nice trees indeed.