Not To Be Missed Podcast!

0soyoung

Imperial Masterpiece
Messages
7,496
Reaction score
12,832
Location
Anacortes, WA (AHS heat zone 1)
USDA Zone
8b
Something interesting from this podcast. Those of you who have been mirai members for a while may have noticed that Ryan has been claiming that auxin is produced in the roots and transported to the shoot tips. He's said this many times with great conviction (claiming that it was based on the latest research results). This goes against everything I've ever heard and I searched the internet for evidence to support his claim - but never found any. During one of the Q&As I brought that up and he was very adamant that he was right. During the podcast though he mentioned this and Wood told him he was wrong and Ryan kind of goes "hmmmph". It will be interesting to see if he changes his claim going forward.

I've been meaning to bring this up on the forum for a while but never got around to it. Maybe someone who keeps up with this stuff (@0soyoung maybe?) can comment...

Ryan is confused if this is what he really believes. I had thought he was being the straight man for Gary to expound, but ....

The root apical meristem does have a very high level of auxin, but it is accumulated from above, not made there. The basic way a root grows is that auxin accumulates at the tip. Auxin goes back up in the epiderm and moves laterally back into the root periderm and down to the root apex - this is the basic 'looping' mechanism by which high levels accumulate in the root apex and is sometimes referred to as the 'auxin fountain'.

There is a bit more detail involving PIN proteins to explaining in detail how all this happens. I suggest reading this paper if you want more in this regard and this other paper if the role of cytokinins (that are made in the root) play in root growth.
 

coh

Imperial Masterpiece
Messages
5,781
Reaction score
6,822
Location
Rochester, NY
USDA Zone
6
Ryan is confused if this is what he really believes. I had thought he was being the straight man for Gary to expound, but ....

The root apical meristem does have a very high level of auxin, but it is accumulated from above, not made there. The basic way a root grows is that auxin accumulates at the tip. Auxin goes back up in the epiderm and moves laterally back into the root periderm and down to the root apex - this is the basic 'looping' mechanism by which high levels accumulate in the root apex and is sometimes referred to as the 'auxin fountain'.

There is a bit more detail involving PIN proteins to explaining in detail how all this happens. I suggest reading this paper if you want more in this regard and this other paper if the role of cytokinins (that are made in the root) play in root growth.

I don't know exactly what he believes but he has made the "auxins are produced in the roots and carried by water to the shoot tips" comment numerous times over the past year. Maybe he was confusing auxin and cytokinins, who knows.

Thanks for the links (@elroy too), will take a look at those when I have enough time to do them justice.
 

PiñonJ

Omono
Messages
1,402
Reaction score
3,332
Location
New Mexico, AHS heat zone 5
USDA Zone
6b
Ryan is confused if this is what he really believes. I had thought he was being the straight man for Gary to expound, but ....

The root apical meristem does have a very high level of auxin, but it is accumulated from above, not made there. The basic way a root grows is that auxin accumulates at the tip. Auxin goes back up in the epiderm and moves laterally back into the root periderm and down to the root apex - this is the basic 'looping' mechanism by which high levels accumulate in the root apex and is sometimes referred to as the 'auxin fountain'.

There is a bit more detail involving PIN proteins to explaining in detail how all this happens. I suggest reading this paper if you want more in this regard and this other paper if the role of cytokinins (that are made in the root) play in root growth.
Thanks for posting links to journal articles. This one doesn’t refute the notion that auxin is produced in the roots. It specifically refers to up-regulation of auxin production in pericycle cells in the outside curve of a bent root. It may have implications for bonsai culture. If you want roots to inhabit a specific area of the pot, put a sharp bend in an existing root adjacent to the area, with the outside of the bend facing the area needing roots!
 

0soyoung

Imperial Masterpiece
Messages
7,496
Reaction score
12,832
Location
Anacortes, WA (AHS heat zone 1)
USDA Zone
8b
Thanks for posting links to journal articles. This one doesn’t refute the notion that auxin is produced in the roots. It specifically refers to up-regulation of auxin production in pericycle cells in the outside curve of a bent root. It may have implications for bonsai culture. If you want roots to inhabit a specific area of the pot, put a sharp bend in an existing root adjacent to the area, with the outside of the bend facing the area needing roots!
Indeed. Glad you read the paper. :cool: Lacking auxin from above, the up-regulation won't happen.

But to the Ryan right/wrong debate, the auxin does not go into the xylem stream. So root tips aren't a source of auxin in any general sense to the rest of the plant.

I think it is difficult to manually bend roots unless you are doing the 'full Ebihara' of a board bed of nails and chop sticks. But, with roots that are younger/smaller/thinner, I am thinking this paper is telling me that one wants a hard particle substrate that makes the advancing root tip zig and zag, this way and that. Pumice serves this bill and so does calcined montemorellite clay (e.g., Turface), for example. Turface MVP is my substrate of choice/convenience; I see this paper to explain why I've always found very good root ramification with it as opposed to garden/potting soils, say. The moisture holding capacity of Akadama may be a good thing, but the suggestion that roots being able to tunnel straight through the grains is not, in light of this paper.
 
Last edited:

Potawatomi13

Imperial Masterpiece
Messages
6,168
Reaction score
4,403
Location
Eugene, OR
USDA Zone
8
Agreed this was most enlightening session. Likely Ryan hmph'd at surprise of prior misunderstanding(maybe embarassment)as respect for Gary and Chris was very evident. Several other great tidbits as well. Will have to listen again(and again)to absorb. Finally learned very valuable lesson of positive/negative energy balance in tree this year. Huge lessono_O and most valuable to know.
 

PeaceLoveBonsai

Chumono
Messages
889
Reaction score
2,979
Location
Franklin, TN
USDA Zone
7a
Great Podcast, a few of my thoughts:

1. Love him or hate him, Ryan is doing a TON to bring Bonsai information to the masses. This is just one of many great resources at Mirai (some free, some not). But almost all very HIGH quality. Just compared to what I could find 3 or 4 years ago, he is really beginning to create a library of great information. There are some here on Bnut and other quality artists in America producing valuable resources (Boon's pine CD's & @Smoke Bnut posts come to mind) But I don't think anyone in America is producing the quantity of quality education that Ryan is.
2. I've started lots of stuff in the ground, then found researching the "how" and "why" and "when" to be very difficult to find and understand. This podcast only reinforces my sense that ground-growing is both very complicated (to do right, nebari/movement/branch placement, etc) and very different than anything having to do w/ bonsai refinement or the normal stuff you might find in books or even on this forum. (Think about how much experience someone like Ryan has, and even he was genuinely mind blown by what the Telperion guys were saying), how are newbies like me gonna find out how to ground grow correctly?
2a. The complications of ground-growing (again to do right) and lack of good education around ground-growing only goes to show, IMHO, that the advice "put it in the ground", is both lazy and often misinformed.
3. Many interesting points in this podcast, but the idea of taking seedlings and wiring for movement and not putting them in the ground until 2-3 years old is very interesting and not something I'd heard before. Also, that they wire, graft, etc while in the ground is also not something I've heard before, or if I had, it wasn't accepted as standard practice.
4. Finally, it makes me really question whether ground growing makes sense for many of us "urban/suburban" bonsai enthusiasts. I always thought, "i'll just put some trees in my grow bed, a chop here, some root work there, and in a few years, voila, i'll have awesome material and save lots of $$$". But the problem with that, I think, is that I need to go deep into the understanding of what it takes to make that ground-ground material truly awesome. It will take tons of research, trial & error, and mistakes before I've perfected how to do it in my own garden. Is that a good use of my time (and space, which is limited for me)? I'm beginning to think no. Maybe it's best to outsource this to the pros, save time and just buy material from the one's who know what they are doing, have the years I'll never have, and the growing conditions/space to create truly awesome ground grown material. I guess I need to save my pennies:)

Anyway, great podcast, highly recommend.
 

Adair M

Pinus Envy
Messages
14,402
Reaction score
34,874
Location
NEGeorgia
USDA Zone
7a
Great Podcast, a few of my thoughts:

1. Love him or hate him, Ryan is doing a TON to bring Bonsai information to the masses. This is just one of many great resources at Mirai (some free, some not). But almost all very HIGH quality. Just compared to what I could find 3 or 4 years ago, he is really beginning to create a library of great information. There are some here on Bnut and other quality artists in America producing valuable resources (Boon's pine CD's & @Smoke Bnut posts come to mind) But I don't think anyone in America is producing the quantity of quality education that Ryan is.
2. I've started lots of stuff in the ground, then found researching the "how" and "why" and "when" to be very difficult to find and understand. This podcast only reinforces my sense that ground-growing is both very complicated (to do right, nebari/movement/branch placement, etc) and very different than anything having to do w/ bonsai refinement or the normal stuff you might find in books or even on this forum. (Think about how much experience someone like Ryan has, and even he was genuinely mind blown by what the Telperion guys were saying), how are newbies like me gonna find out how to ground grow correctly?
2a. The complications of ground-growing (again to do right) and lack of good education around ground-growing only goes to show, IMHO, that the advice "put it in the ground", is both lazy and often misinformed.
3. Many interesting points in this podcast, but the idea of taking seedlings and wiring for movement and not putting them in the ground until 2-3 years old is very interesting and not something I'd heard before. Also, that they wire, graft, etc while in the ground is also not something I've heard before, or if I had, it wasn't accepted as standard practice.
4. Finally, it makes me really question whether ground growing makes sense for many of us "urban/suburban" bonsai enthusiasts. I always thought, "i'll just put some trees in my grow bed, a chop here, some root work there, and in a few years, voila, i'll have awesome material and save lots of $$$". But the problem with that, I think, is that I need to go deep into the understanding of what it takes to make that ground-ground material truly awesome. It will take tons of research, trial & error, and mistakes before I've perfected how to do it in my own garden. Is that a good use of my time (and space, which is limited for me)? I'm beginning to think no. Maybe it's best to outsource this to the pros, save time and just buy material from the one's who know what they are doing, have the years I'll never have, and the growing conditions/space to create truly awesome ground grown material. I guess I need to save my pennies:)

Anyway, great podcast, highly recommend.
I agree!

I’ll let Telperion do this:



B1908B18-A12F-4B68-BAA2-65EE48D3504C.jpeg

So that I can do this:

A592E324-CC7B-4CA3-8162-BB8C274F95D9.jpeg
 
Top Bottom