Trunk Copping Fundamentals

[jimlau]

When you do a trunk chop, and wire a branch to be the new leader, the taper can be had to transition from the now-thinner trunk at the level of the new leader to the new leader. But if you spin the tree 90 degrees, the trunk width is not reduced at the height of the new leader, so there is a sudden difference in width between the trunk and the new leader.

so how can the new leader have a smooth tapered transition in the front, with the similar trunk diameter at its height, at the same time the same branch provide for a smooth taper with the side view wider trunk?

 

[jk_lewis]

so how can the new leader have a smooth tapered transition in the front, with the similar trunk diameter at its height, at the same time the same branch provide for a smooth taper with the side view wider trunk?

TIME! Lots of it, and successive chops. Bonsai can't be grown in a week or even a year.

 

[jimlau]

but how can 1 branch ever match up with a 2 different-width trunk? at the height of the new leader, won't the trunk in the front view always be narrower than the trunk from the side view? so how can a symmetrical branch blend to 2 different widths?

 

[0soyoung]

but how can 1 branch ever match up with a 2 different-width trunk? at the height of the new leader, won't the trunk in the front view always be narrower than the trunk from the side view? so how can a symmetrical branch blend to 2 different widths?

I think you are on track and I think it is why formal uprights are not made by chopping trunks. If you are going to chop, then you should be making a trunk with 'movement' - this helps to disguise the chop(s). You might find this article at evergreengardenworks a worthwhile read.

The other way to produce taper is with lots of branches trimmed like an exaggerated teepee during development (long branches down low, shortening with position up the trunk). I think this is the only way to produce a formal upright trunk (that doesn't have the faults you are concerned about).

 

[jimlau]

I guess it's not safe to try a small trunk chop on the back side, which would result in 3 sides being cut?

 

[october]

Here is a link to one of the best articles on the subject. It is very clear and straight forward.

Rob

http://bonsaijournal.com/beginners-trunk-chop-101.php

 

[jk_lewis]

Formal uprights can be made by LOTS of small chops so you don't have a sudden decrease in girth. By the time you have a nicely tapered upright tree, you may have chopped 20 times -- over 30 years. AND have grown it in the ground for that time.

If you are trying to chop an already thick but taperless trunk down and end up with a sudden decrease in size, you made a poor choice of tree to work with in the beginning. Or, you chose a style for your plant that was totally inappropriate for the specimen.

It's the old silk purse out of a sow's ear syndrome; you are NOT going to produce a class act bonsai out of a junkyard tree.

 

[brewmeister83]

When trunk chopping it's also important that you don't chop too soon in the tree's development. If you're growing stock in ground, make sure the base of the trunk is the right size first. Read this to see what I mean:

http://bonsai4me.com/AdvTech/ATCollectedBeechProgressionSeries.htm

 

[thailand-steve]

i'm far from an expert on this but have been wondering about this for my ficus which is already quite wide at the base but needs some serious taper.

i like this video http://www.youtube.com/watch?v=Dqr_tM0rk1M

in his situation he is trying at add a low branch but i can't think of a reason the same technique could not be used for a new leader in thick truck. just angle the thread graft up at a 45degree angle or more if you can and when the graft has taken hold, lop the top off. i think for this to make a nice transition you would need to thread graft something about 1/4 to 1/3rd the dia of the trunk. i don't know how practical that is. interesting to try however.

has anyone tried this?

 

[Bill S]

Carving and wound healing also close up the differances.

 

[Paradox]

Related to this, I've been wondering something. How soon after a chop do you pick your leader and start getting rid of the rest?

I've got a tree that I chopped late last winter. Its a birch but the same question would apply if it were a maple.
It has come back pretty strong and is now exploding with shoots all over the place.
Do I let these go this year and feed the crap out of it to let the tree gain strength or do I start eliminating the unwanted ones now in favor of the future leader?