Trunk Chop Thoughts

Ian_Homer

I would have thought just before the re-potting season in your area (very early spring) prior to the sap starting to rise too quickly. This would give the tree a full seasons' growth in order to heal. The cambium layer would also just be receiving more from the root system and would serve to "fuse" together quickly.

You will need to prevent any undesired growth popping around the cut - since this will deplete strength higher up the new trunk.

It would also be an advantage to keep top growth restricted in the first year working more on refining the lower branches.

This would force the tree to send even more energy up past the cut in an effort to replace the removed foliage - although a trees natural habit is to send energy to the tip first then elsewhere afterwards. This helps in establishing thickening of the lower section more. Providing things work well after the first season, the next year can be used to refine and allow extension to any branches forming on the new top section - and you should have a well established taper !

Anyone else with thoughts ? . . . . . . . .

__________________
help save The Vulcan...
Return to Flight

Advertisement

Attila

My favourite time for doing trunk chop/new leader training thechniques for conifers is the end of the growing season. Depending on where you live, this can be a different month of the year. I like to catch just the end of the current season's growth, so a small callus forms before the dormancy begins and so the new shape is already solidified. Since it is the end of the season, the sap loss is not as bad as during the first part of the season.

However, this is the worst time for certain deciduous species prone to die-back, such as birch, alder, etc (birch, alder, and relatives shouldn't be touched after mid-season). So, for the rest of the deciduous crowd, I do it during the first part of the growing season. With some members of this second crowd, the ones that don't take well heavy pruning (for instance beech family) I rather do it very early.

Attila

Will_Heath

yes, thanks attilla, I was thinking fall, I guess I'll wait till then post pics. Thank you.

Panamaniac

Any updates to the experiment? Any pictures to better visualize?

Thanks!

Will_Heath

Nothing I am ready to post. I have done a few using this technique and have 10 more marked to do this spring. So far the results are excellent. I will be posting a photo journal this spring.

Good luck.

Will

bonsaial1

Just some random thoughts... nothing scary

Thought 1. I have bent trunks on redwoods and foemina junipers up to 2" thick with iron rebar and blocks with a couple turnbuckles. I would think this might work with any number of species.

Thought B. Most grafts seem to bulge on the graft line for some time. I would think there would be an enormous amount of scarring going on near a cut this big. ( If the cut is not that big, why cut it?)

Thought 3. The graft joint will be very weak for at least 5 years. No bending, no moving whatsoever. It takes at least five years of over growth scar wood to make an acceptable union to allow bending or wiring.

Thought IV. Grafts of a size much over 1/2" are not very reliable. They can be done, but are hazardous. If it fails, I would think,Shari.

Thought E. How are you going to hold it closed? If an iron bar is the idea, why not just fasten the smaller part to the iron bar and torque it into place and tie off the iron bar at the base of the tree. Or add a block as a fulcrum.

Thought 6. Why not just procure the appropriate piece of stock that works for your application?

Thoughtless, Al

__________________
I been kidding the last seven years.
no.... really!

Will_Heath

All good points Al with no real answers. This is simply another option to add to the tool box.

This year I performed this technique on a larch, I used a heavy chopstick (I like the idea of rebar) wired above and below the chop. It has held it in place and the graft took well. I did achieve a perfectly straight new apex as desired with no noticeable bulge as of yet.

Keep in mind that I will not fully realize the full potential of this technique for another 5 years or so, meanwhile I will do 10 more this spring, different species. We will see, after all, there's no harm in experimenting.

Will


Edit: on the same subject: A bulge can always be carved back. As a straight taper is the goal the trunk will not be moved, so not to worry about the weak point.

TUNA

What do you guys think about this. http://www.bonsaisite.com/chopping.html

Its also on Brian's Bonsai page with a little more info, but I dont know to link to it directly. Its in advanced techniques section under trunk chopping.

Tony

Tuna, I think it will work with a fast growing tree in the right climate. Note that Brian is in Australia. I think that doing this to a boxwood in zone 5 would get you a srcar that you'ld have to hide for 30 years.

Tony