San Jose Trunk Development

[majohnson]

In watching the video series from Lindsay at Bonsai Farm, there is a scene showing removal a small strip of bark from the trunk of a Shimpaku. The reason behind it seems to be for development of the trunk.

If someone can provide me with further explanation, and if the technique works on other junipers.

 

[Brian Van Fleet]

Removing a strip of bark creates a wound that the tree heals by forming callous of cambium layer around the wound.

It should work with any juniper, you just need to be strategic about where you place the wounds. If you want the trunk to thicken visually, you'd wound the front and the cambium would swell on either side of the wound, making it appear wider.

These photos show the result of 6 months of this technique.

 

[chrisbotero]

Ive been cuious about this also. In the video it seems that by cutting a spiral up the trunk it will cause there to be movement over time as the live vien swells. I dont see how this can work. Maybe they were wiring in the movement and then cutting the spirral but the guy in the video doesnt say that. I have some cuttings that I will toy around with over the next few years. I will try this method and also wire in movement to see what might work better.

 

[Brian Van Fleet]

I'd be very hesitant to carve spirals up the trunk unless you understand how veins and water lines work in trees, as spiraling effectively girdles the trunk, forcing the tree to create new waterlines between the branches and roots.

Kathy Shaner teaches carving ovals as shown in the images posted earlier, then, over time (like every 6 months to a year), creating more ovals, and even connecting some, so the exposed deadwood has varying depths and textures. It's also less stressful to the tree than carving a spiral all the way up the trunk.

 

[chrisbotero]

I need to clarify; the guy in the video says he would only go once around the small tree, not spiral up the entire thing. I can see this causing the same problem if the waterlines run exactly vertically up the trunk. Maybe only cutting half way around the tree and spreading out the cuts one or maybe two per year would let the new waterlines develop.

 

[woodguy]

There is a good article in the March/April issue of Bonsai Focus called "Timber Twisting" which covers this. Three different trees are shown to outline how this technique can be used to get different effects. There is a Dawn Redwood that has a spiral developed in it. The key seems to be to take your time and to re-damage the bark/cambium before it heals over the wound.

There is also a San Jose featured where the trunk has been developed using this technique. Good before and after photos.

 

[majohnson]

Sa Jose Trunk Development

I have seen picture of a couple Redwood Dawns, where they cut spirals the full length of the tree. They almost look like a barber poll, a little to artificial for my taste.

I am going to play with a couple of trees this spring, doing it in small section makes since.

Thanks,
Mark

 

[woodguy]

I agree with the "barber poledness". I only mentioned the DR because spiraled trunks were mentioned earlier in the thread. What I found to be of value in this article was that the author uses the bark removal to redirect the flow of nutrients to get different effects. On the San Jose the effect was to create exaggerated live veins, giving the trunk a ton more character. There was also a Yew that had one side of the trunk bulked up using this process to remove a slight curve and get a straighter trunk. Good progression photos really show how it develops.