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Saturday, August 21, 2010

Making a big bend

Todays post is about making large trunk bends. The material is a 12-15 year old grafted Atlas Cedar. The height is 48" and the width of the base at the soil line is about 2 3/4". The area above the graft has a slight reverse taper which I hope to be able to hide.
Here is the tree before work started.

The first step is to prepare the trunk for bending. I begin by wrapping wet raffia  tightly around the trunk being careful to overlap each turn so that there are no gaps.



After the raffia wrapping, I placed three large wires parallel to each other on the trunk to give added support to the area to be bent.



I then add more raffia on top of the wires at the areas where there will be the most stress. A piece of rebar is then placed on the trunk being tied on at the place where we want the bend to be . Because of the thickness of the trunk we need the extra leverage provided by the rebar.



Using the bar for leverage I make the first bend. I do this slowly and carefully listening for any cracking sounds. This is one slight cracking noise just before I stopped but it should be no problem. Its not the first crack that is of concern but the second one right after the first.


At this stage I use a guy wire from the tree to the top of the pot to hold the trunk in this position. I removed the rebar to reposition it for the next bend.
Again using the leverage provided by the rebar  I slowly bring the trunk further down towards the ground.  Again taking my time and listening carefully for any sounds of cracking. At this stage I use a wire tied around the pot and to the trunk to hold the tree in position.

Now I will use the guy wire to pull the trunk even closer to the pot. After I get it into the  desired position I lightly trim and  wire all the branches, and position them . You can see the difference from the above picture.
This will be the new front of the tree when it is repotted next spring. For the next couple of months I will leave the tree to recover from the stress of being turned upside down. By next March I anticipate that the tree will be healthy enough for repotting. Other than water and fertilizing and light pinching I won't be doing much until then.
This same technique can be used on pines, junipers and other trees as well.
I hope you enjoyed todays post. Please feel free to leave any comments.

6 comments:

  1. Hi Bob,

    Thank you for posting this; I have a couple of questions: How soon do remove the first layer of raffia from the three. What do you do if anything to help healing of small crack in the three’s trunk that may happen during bending?

    Thanks again!

    Julio C Almeida

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  2. Thanks for the comment and questions. I leave the raffia on pretty much until it starts to fall apart on its own usually 12-18 months than I remove it and the wire. Small cracks I don't worry about they'll heal themselves or more accurately they'll seal off the damaged areas which forms scar tissue that actually helps in holding the bends. The raffia helps keep that small cracking from becoming large cracking.

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  3. Hello Bob,

    Thank you so much for answering, it all makes sense. What about the wires you placed along the trunk, what type of material are they. Are these steal wires – the kind that return back when bent or a malleable material such copper?
    I am getting ready to bend a Japanese Red Maple that have a 2 ½ in trunk and all this information is very appreciated.

    Thank you,
    Julio C Almeida

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  4. You're welcome. Thank you for reading. I would not try to make a bend nearly this severe with a maple. The wood is not nearly as flexible as a conifer.Bending that size trunk on a maple would be problematic.

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  5. Hello Bob,

    Thank you for all the previous answers, I greatly appreciate your willingness to share your knowledge.

    Regarding that Japanese maple tree, I really need to introduce some bents to the trunk in order to bring down its height. I was thinking in making a few ‘V’ cuts in the inner side of the bent to facilitate the operation. What is your experience/recommendations in this regard? The trunk is about 2 ½ inch: how deep can I go with the cuts? Any special procedure or product to facilitate the healing?

    Thank you so much for your time and patience!

    Please note that English is my second language; I apologize for any grammar errors.

    Regards,

    Julio C Almeida.

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  6. Hey Julio
    Why don't you post a picture on my facebook page and I'll see if I can give you any suggestions. It would be helpful if there were something to judge scale by in the photo.
    https://www.facebook.com/pages/Kimura-Bonsai-and-Landscape-Nursery

    ReplyDelete