Grafting theoretical question for tighter bends

[NaoTK]

We usually insert the scion to match the direction of growth (left) but why can't we do the right for better branch position on junipers etc? If I think about it, the cambium will still match and the tree will sort it out. I've just never seen an example of the right.

I will try it regardless this year on juniper and persimmon.

 

[Ruddigger]

I’ve seen Ryan Neil do it that way, but it was on a branch, not a trunk. I think he said it wasnt as foolproof as the normal way.

 

[mwar15]

Some of it is the natural flow, think if the flow was going up and take a slight angle compared to a 180 degree turn. I think with solid technique and after care it is doable. I have done it with JBP.

 

[yenling83]

On Junipers you 100% can do that. I've seen it done at Aichi-En with success.

 

[Bonsai Nut]

I've seen it done. It all depends on the situation - and which angle will yield the best aesthetic. But if you are asking "can" it be done? Yes definitely.

 

[Bonsai Nut]

Related to this question - if I have a pine branch that has gotten too thick, I will sometimes graft small/young branches off the bottom of the branch where it meets the trunk. In the case the graft will be horizontal with a downward angle - versus if you graft on top of a branch it will be horizontal with an upward angle.

 

[Ruddigger]

Getting ready to graft that San Jose?

 

[NaoTK]

Getting ready to graft that San Jose?

Yeah after shohin school I'm working on all my junipers and have piles of cuttings. My Japanese books recommend Feb for grafting. Will probably do itoigawa. Actually Dave was over here a few weeks ago and signed off on it "great idea!"

 

[0soyoung]

There is a thing called Polar Auxin Transport (PAT) in the cambium that defines 'up' versus 'down'. It is due to 'PIN proteins' in the cell wall being on one end of the cell. An 'upward' graft (as you show on the left in your diagram) the PAT flow is continuously down on the underside of the scion and along the stem below the graft point. Above the PAT flows are opposite - hence auxin will tend to build up at the junction on the top side of the scion. Placing the scion 'upside down' (as shown on the right-hand diagram) doesn't actually change anything with regard to the PAT flow - it is continuous below and in conflict above.

As we should all know by now, excess auxin leads to the production of ethylene which cause enhanced radial growth A free scion is analogous to a cutting, in that it must survive on its own until NEW xylem has been grown to connect it to the water supply of the mother stem. The faster this happens, the better are the chances of success. So, one wants to match the cambium at the position where the PAT streams are OPPOSITE = match cambiums on the stem side with 'up' grafts, on the outside/flap side with 'down' grafts.

Of course, it is easier said than done (aligning cambiums ).

 

[Ruddigger]

Yeah after shohin school I'm working on all my junipers and have piles of cuttings. My Japanese books recommend Feb for grafting. Will probably do itoigawa. Actually Dave was over here a few weeks ago and signed off on it "great idea!"

I thought you were set on Kishu?

 

[Wires_Guy_wires]

There is a thing called Polar Auxin Transport (PAT) in the cambium that defines 'up' versus 'down'.

I view this differently. Polar transport means in my book that it can(!) go against a stream, but it doesn't have to. It can move in all directions, and going against the flow is just one of the options. I'll throw in the more recent discovery of LAB (local auxin biosynthesis) on top of that. Not all auxin transport has to be strictly polar, it should be in the literature describing it. It's just one of those hundreds of things that can - if needed - go against the sapflow.
Meaning orientation of the scion, when it comes to auxins, doesn't matter.
Sap flow itself seems to be the major factor of success.

 

[NaoTK]

I thought you were set on Kishu?

yeah changed my mind... I like the texture of kishu but the color is too uniform and doesn't change color with season as much as itoigawa. Itoigawa is sort of bronzey green right now. And for this particular tree I think the texture of itoigawa will be better, sort of wild and pointy vs soft and compact. I don't know I can always change it again!