1: What is the “Van Meer” technique?
To put it simply: a technique that helps the healing over and closing of large cut wounds on trees! I tested and developed this technique over a period of more than 15 years on my own trees and on those of my students, and I think it is now tested enough to share it with other Bonsai enthusiasts! Most of the tests were preformed on deciduous trees but it can also be done on evergreens!
2: How I came about to develop this wound treatment technique.
I started with Bonsai in January 1990, when my wife gave me an Ulmus Bonsai as a birthday present. I was immediately hooked and wanted to learn every thing there was to know about this amazing hobby and art form! I wanted, like in my real life, to learn and teach it by my self in my own way and at my own pace, so I started to collect every Bonsai book that I could get my hands on.
I also subscribed my self to 4 different Bonsai magazines! One of those magazines was “Bonsai Praxis” – an obscure German Bonsai magazine published by Wolf -D. Schudde, a Bonsai artist. Although his radical styling ideas that were not really my cup of tea, his work was original to say the least!
In his magazine, meant mostly for the beginning Bonsai enthusiasts, he preferred to work on really hopeless material and the end results were usually not that good. So after a few years, I found I had out-grown his magazine and stopped my subscription! But I have to give him the credit that he deserves for planting the spark in my mind that led to the development of this particular technique!
It must have been somewhere in the mid-nineties when he wrote in one of his magazines about how he removed a big branch. Now, this in itself is not special, but what he did to help that large wound heal over faster and better, certainly was!
He used a section of the bark from the branch he had just removed, and folded it over the wound to close it some more and to help the healing process! And I thought that this was just a brilliant idea!
Wolf-D. Schudde died a few years ago, so I had no change to thank him in person for his idea, but I like to honour him in this way! Thanks Wolf for planting the spark! After he died, a few German artists took it upon themselves to keep his Bonsai artwork alive for the world to see. I think this is a great thing, because he, like Nick Lenz (USA) showed us in the nineties a different way to use Bonsai as an art form! His original and unique ideas, like the use of barbwire and coloured gravel in his creations, still pops up every now and then in Bonsai shows around the world! Wolf -D. Schudde was a true visionary artist in every sense of the word!
3: Why I named it the “Van Meer” technique?
In the late Nineties, after testing and further developing this technique successfully, I decided to write a short article about it for the only Dutch Bonsai magazine “Het Bonsai Blad”. It was published in the 22nd edition of the magazine, and was entitled “Snoeien zonder littekens” (cutting with out scars)! This magazine was later bought by Farrand Bloch and his partner, Rene Rooswinkel, who named it first ”Bonsai”, and later “Bonsai Europe”, until finally it became the international Bonsai magazine that we now all know as “Bonsai Focus”.
Years later, I was contacted by a Bonsai friend who told me that on the Belgium and the Dutch Bonsai internet forums they were discussing a “ Van Meer technique”?! He asked me: do you know what that’s all about? In those days, I still had no personal computer in my home, so I did not have a clue! He printed it out for me to read, and only then I realized that they were discussing my years-old article about wound treatment, and that they had started calling it the “Van Meer technique“! Now almost 15 years later, I started to write down all my experience with this technique to share it with the world, and decided to use this name that had been used by others for over a decade on the internet. So it is not that I find it important that this technique is named after me or anything like that. That’s not really what I’m about!
So now we can really start the show!(8)
Note: The safest time to perform this technique is from early Spring to early Summer and even then only on thriving and well established trees with a healthy root system!
This large wound would than be hollowed out a bit to allow the wounded bark to heal over the large wound better. Finally, the wound would be sealed with cut paste to prevent drying out and infections.
From then on, we would keep our fingers crossed hoping that this large wound would heal over, which in reality most of the time will not happen at all or only partial. This leaves us with a unsightly, large, open scar with an ugly bulging rim on our tree!
This occurs especially on species like Hawthorns, Beech, Olive and Pine! Now this is where my technique comes in handy!
Lets have a closer look at this sliced section of a tree branch or trunk. There is the inner sapwood that is like the skeleton or inner foundation of a tree. Then there is the all-important life-giving cambium layer that transports everything that a tree needs to stay alive. And last but not least – the outer bark that protects the tree just like our own skin does for us. For my technique it is important to understand that the outer layer of a tree, which heals over a wound, consist of the cambium layer and the protective outer bark layer.
Now, I know it isn’t a pleasant thought, but imagine that a leg or an arm is amputated on us humans. When possible the surgeon will always leave a flap of skin from the removed limb to fold over the wound to close it! And that is exactly what my technique is all about! Closing wounds on a tree with its own skin, or in a tree’s case – with its own bark!
All we need to do in theory, is to remove the inner wood so that we are left with a living layer that consists of a thin layer of sapwood, the cambium and it’s outer bark to fold over the wound! Simple isn’t it?! So how dies this work in practice?
This should be done without damaging the all-important cambium layer! And in such a way that a thin layer of inner wood is left in addition to the cambium and bark! This thin layer of sapwood prevents the bark from collapsing or tearing when bent! The green line represents the important cambium layer!
I will use power tools, different sized chisels or both to carefully remove the inner wood. It all depends on the size of the trunk or branch that needs to be hollowed out! Whatever you prefer or are comfortable with is fine, as long as you don’t damage the all-important cambium layer! And make sure that you don’t remove too much of the inner wood going down or inwards in your stump! The bottom of your wound should be slightly deeper than the surrounding bark, leaving enough room for the slightly thicker bark that you will later bend down! When the folded bark is bent in place, it should be flush with the surrounding bark! Not deeper! Slightly higher is fine though!
(top) With a clean scalpel or thin, sharp hobby knife, we make evenly spaced angular incisions in the flap, and then remove those wedged shaped pieces of bark. Now, we can start to carefully bend the pieces of skin one by one into place. If there is still some overlap, you simply cut some more away until it all fits! Don’t worry when there is some space left between the folded sections of skin, they will heal over nicely! (bottom) In the drawing you can see that I did not try to close the whole wound in one go, that is because I have found out that on really large wounds it becomes to difficult to folded the skin into place. It is easier to close 1/2 to 2/3 of the wound! The rest of the small open wound that is left will heal over pretty well when the folded skin has grown together!
Treating a large wound left from cutting off a side branch.
Note that we are using a skin flap from below the wound, because that is the direction of the upwards sap flow from the roots to the top and that will increase our success rate! On a larger branch (which leaves a larger flap), it is better to cut out a wedged shaped piece of bark so that the skin does not break or fold to much
Let’s look at an actual example.
The red arrow points at a point were the skin flap already has the desired thickness. Just left of the arrow you can see the strong shoot that will become the new top. This shoot will grow vigorously in the future and that will help to close the wound even faster!
The red arrow points to the wound. On the right of the arrow you can see the new top and on the left a new side branch. Both have helped the wound to heal over easier and faster! This is what you basically do when you use the “Clip & Grow’ method! Let grow to length, cut back to new growth, let new growth grow to length, cut back to new growth….until the branch structure is there! When done right, this creates perfect taper and natural movement. I prefer a combination of wire and clip & grow!
The red arrows are pointing to the rim of the old wound, so a large section has successfully closed over without the normal bulging, making the transition from bark to wound smoother! The green line shows that the whole healed wound has a nice rounded shape to it, instead of the unnatural sharp angle one gets when a large scar is left to close on its own in the usual way! The wound is not completely healed over, but still looks way more natural that otherwise, and the tree will close this small scar in the next couple of years with out any problem!
Creating new roots from a stump
This next example is of the first time that I tried this technique on roots!
The red arrows points at a 4cm-thick root stump that was cut on the hill when the tree was collected. Although this unsightly root was situated at the future back side of the tree, I still wanted it to look more natural! So as soon as the stump had made some strong new side roots just above the cut, I decided that it was safe to start working on it!
Then I carefully removed, with a tiny drill bit, the inner wood from below the bark until I was left with 2 skin flaps. (middle bottom) The red arrows point at the bark/skin flaps.
Then, I folded those bark/skin flaps back over the prepared inner wood and secured them with 2 pins. Then cut past was applied.
Proof that it has worked! The single old root stump now looks like two natural roots and nobody will notice that they were hand made! It takes some time, but it is worth the wait and the effort!
Variations of the same root technique
This small Hawthorn was collected in Wales (UK) 2006. After collecting, several root stumps needed to be worked on. The red arrows point at the 2 red pins I used to hold the skin flaps on this important side root stump in place. This is what I have done to it earlier.
The red arrows point to where the stump ends. You can clearly see just how bad a hawthorn heals over large wounds! It bulges and will never close completely! The root stump itself is too long and has reverse taper to it, so it needs some help to become presentable, especially because it is in plain sight and important for the stability and the overall image of this small tree!
And another root technique variation from the same Hawthorn
So we have come to the end of this little article of mine, I hope that it was understandable and that you all will try this simple technique on one of your own trees in the future! There is no guarantee that it will always work. But even so, all that can happen is that you will be left with the same wound that you would have if you did not used my technique at all! So give it a try and share your experience with the rest of the Bonsai community! And don’t be afraid to experiment, as long as it is done with respect for the material that we use to express ourselves – the trees! After all, our art is made from living beings and they are helpless and need us to stay healthy and happy!
Next thing for me to try with this technique, is to replace or relocate whole branches or roots on a tree! I will keep you all posted about my progressions!
And last but not least: I don’t mind at all what name you will use for my little technique as long as you give it a try!
Success and keep them small,
Hans van Meer.