JBP Roots

[mrcasey]

The consensus that I've seen has come from mostly youngish Americans who've apprenticed in Japan.
Ryan Neil, Bjorn Bjorholm, Michael Hagedorn, and Boon (I think) are all proponents of NOT completely bare rooting pines during a single repotting. They either advise partial or half bare rooting. But guys from Europe and Britain like Colin Lewis, Graham Potter, and Walter Pall (in some cases) advocate complete bare rooting. One thing I've noticed about the latter group is that they will sometimes not remove ANY roots when performing a complete bare rooting.

p.s. When Ryan Neil launched one of his first free beta tests for Mirai Live, he repotted a big shore pine. I peppered him with questions about the old soil in the root ball. I'll never forget that he stated that some of the old mountain soil would stay in the center of the root ball right underneath the trunk for over a decade. After two or at most three repots, the pines of Boon and his students will have ZERO field soil in the roots.

 

[hemmy]

I'll never forget that he stated that some of the old mountain soil would stay in the center of the root ball right underneath the trunk for over a decade. After two or at most three repots, the pines of Boon and his students will have ZERO field soil in the roots.

Not speaking to Boon’s repotting schedule, but in general, one could point out that 2 or 3 repots might cover well over a decade.

 

[Walter Pall]

The consensus that I've seen has come from mostly youngish Americans who've apprenticed in Japan.
Ryan Neil, Bjorn Bjorholm, Michael Hagedorn, and Boon (I think) are all proponents of NOT completely bare rooting pines during a single repotting. They either advise partial or half bare rooting. But guys from Europe and Britain like Colin Lewis, Graham Potter, and Walter Pall (in some cases) advocate complete bare rooting. One thing I've noticed about the latter group is that they will sometimes not remove ANY roots when performing a complete bare rooting.

p.s. When Ryan Neil launched one of his first free beta tests for Mirai Live, he repotted a big shore pine. I peppered him with questions about the old soil in the root ball. I'll never forget that he stated that some of the old mountain soil would stay in the center of the root ball right underneath the trunk for over a decade. After two or at most three repots, the pines of Boon and his students will have ZERO field soil in the roots.

Absolutely NOT. I try to avoid or postpone repotting as far as possible. And if I do it I would never ever bare root a conifer. Where have you got this misinformation from? I would also avoid bare rooting a broadleaf tree if possible. Plus on all trees I would cut as few roots as possible - often not a single root.

 

[Shibui]

I’m noticing that you have a “humid subtropical climate,” which is ideal for the JBP. I’m wondering if that bolsters your successes, in addition to good technique and timing.

When do you time this work?

Not sure that I'd describe this area as hot, humid, sub-tropical. It does depend what you compare with but our summers are hot and reasonably dry with regular daytime high temps around 40C. Winter overnight goes just below freezing most nights for a couple of months.

I start digging trident maples in July - just after mid winter. Pines and junipers are dug and pruned when the maples are done so from around August which is getting toward the end of our winter.

Since you bring it up, do you have any ideas as to why there seems to be near-consensus from professionals (...and high-level practitioners) that its not safe to bareroot pines? For that matter, do you know any professionals that teach barerooting pines?

I know very few professional bonsai practitioners personally. They are not exactly thick on the ground over here so the only contact I have is through written material and websites.
As to consensus, I've been at this long enough to have seen many changes of direction and advice from the leading lights of bonsai and I expect there will be more changes of methods and technique in the future.
All I do is offer direct experience. Anyone is welcome to consider it or ignore it.

 

[Brian Van Fleet]

Absolutely NOT. I try to avoid or postpone repotting as far as possible. And if I do it I would never ever bare root a conifer. Where have you got this misinformation from? I would also avoid bare rooting a broadleaf tree if possible. Plus on all trees I would cut as few roots as possible - often not a single root.

Which is exactly how you get away with “repotting” in mid-summer.

 

[Sticks 'n' Triangles]

It amazes me how many myths are used as fact, perhaps we have discovered one more in this thread.

What about the use of that mycorrhizae powder when collecting and/or bare root repot?

 

[Japonicus]

$109.95 — no tax. I’ve been tempted to get another. The nursery has at leaf a dozen remaining.

I thought it had a beautiful blue hue to it. That explains it.

 

[Mike Corazzi]

Which is exactly how you get away with “repotting” in mid-summer.

Or fall, or spring, or winter.

 

[mrcasey]

Not speaking to Boon’s repotting schedule, but in general, one could point out that 2 or 3 repots might cover well over a decade.

Strictly speaking, this is true, but several of Boons students here have suggested doing a half bare root one year and the other half one or two years later. Also, as I don't still have the chat transcript from Ryan's video, I was trying not to misrepresent what he said, but I believe(?) he mentioned going quite a bit longer with that old mountain soil under the 'shin'?

 

[mrcasey]

Absolutely NOT. I try to avoid or postpone repotting as far as possible. And if I do it I would never ever bare root a conifer. Where have you got this misinformation from? I would also avoid bare rooting a broadleaf tree if possible. Plus on all trees I would cut as few roots as possible - often not a single root.

Thanks for the correction, Walter.

 

[Alain BERTRAND]

What about the use of that mycorrhizae powder when collecting and/or bare root repot?

Not a problem.
Fungus are micro-organisms. If washing surfaces with plenty of water were a way to get rid of micro-organisms, asepsis in hospitals would be far easier.

 

[Japonicus]

For that matter, do you know any professionals that teach barerooting pines?

Pg 133, 3rd paragraph of the Bonsai Today Master series, (a culmination of unattributed techniques
from Bonsai Today issue 17 and written by Wayne Schoech in the JBP section of the "book").
"After cleaning off the old soil..." and illustrated using a garden hose.

I too leave old soil when I repot, getting more each time. So "long hauler" here as well agreeing
with and exercising the decades approach on pine and juniper. Have never HBR'd, never plan to, but it works.

 

[parhamr]

Not a problem.
Fungus are micro-organisms. If washing surfaces with plenty of water were a way to get rid of micro-organisms, asepsis in hospitals would be far easier.

I hear you on this, and you’re not wrong about that specific case, but it reads as a full on non sequitur. A hospital aims to reduce pathogens by something like 99.9999 percent to prevent any of them from reaching spaces where they do not belong. In other words it’s an exhaustive problem with logarithmic or exponential analyses.

The roots of a tree — for a species where functional and thorough symbiosis is required for respiration to continue approximate to its current state — is something where margins of 25 to 75 percent seem acceptable. This is a linear or cubic problem space.

Apples to oranges. I’m not saying fungal supplementation is required, but I’m saying that this is the opposite of basic germ theory.

 

[Alain BERTRAND]

Empiricism rules. As I always wash pine roots (like any other tree), never add mycelium, as the trees don't die and as they are usually full of mycorhizae a few month later, I do think that your supposition that mycorhizae should stay functional for the tree to survive is wrong.

BTW, almost any tree can establish symbiosis relationship with fungus. If we care so much for mycorhizae in pines it is only because we can see them though we can't for most trees. It is sample bias not biological reality.

 

[River's Edge]

So it is said that you should not bare root JBP.

This is in reference to the amount of work done at one time with most developed and mature JBP. Very young trees are more vigorous and it is possible to do more work with successful results. Conifers in general are best repotted in stages rather than bare rooting. A variety of repotting techniques have been developed to suit the conditions and species that are worked with. For JBP the basic premise is 1/2 HBR when repotting on a regular basis after development and during refinement and maintenance of the tree.
The situation is separate if the tree is collected or being adjusted from nursery soil and pot conditions. The understanding being that these situations require more aggressive overall work and it is best staged over time with recovery allowed between repotting sessions.