Advice on JBP approach graft

[pitchpine]

Hey guys,

Backstory: a couple years ago I tried an approach graft on my first Japanese black pine, which was a workshop tree and still early in development. My goal was to improve the lower trunk, which due to some twists looks like it has a bit of reverse taper even though it doesn't really. So I grafted the lowest branch (#1 on the photo), which was in a poor location on an inside curve, around to the opposite side and in a lower position. This spring I realized the graft had failed because I made the cut too shallow and didn't secure the branch tightly enough, and as it thickened it got pushed completely out.

So I recently decided to try again at a slightly lower point on the trunk (green circle on the photo) using a small side shoot of the original donor branch (#2 on the photo). I'm pretty sure this time I made the cut deep enough and nailed the scion securely in place. (FYI, the dashed lines show the parts of the branch that are behind the trunk from the viewpoint of the photo.)

I know I want to prune the original branch back to the grafted offshoot, but am uncertain as to the proper timing. If I want to maximize both the chances of the graft taking and the speed at which it does, should I cut #1 back to the juncture with #2 all at once, or in stages? And should I make the first (or total) cut now, or wait for the needles to harden off?

Thanks in advance for any advice!

Laura

 

[Adair M]

It takes at least a year for it to take, so be patient.

You can start to weaken the feeder portion of the branch. Two ways: 1) slice off a section of the bark and cambium below and above on the section of twig feeding the graft. This will force the tree to use the graft to feed the scion, not the old stem. 2) loop a piece of wire around the feeder stem. Twist it tight with pliers. As if to strangle it. Tight enough to just barely begin to cut in. Again, this restricts the glow of nutrients, and makes the scion use the graft junction.

Good luck!

 

[0soyoung]

It takes at least a year for it to take, so be patient.

You can start to weaken the feeder portion of the branch. Two ways: 1) slice off a section of the bark and cambium below and above on the section of twig feeding the graft. This will force the tree to use the graft to feed the scion.

Water and nutrients are drawn through the xylem (wood) by the foliage. Sugars made by photosynthesis (food) are conducted downward (away from the foliage toward the roots) in the phloem or inner bark. Auxin produced by the growth tip/buds and foliage is move down the tree from one cambium cell to the next.

The cambium causes radial growth. Cambium cells divide. Those toward the inside become xylem. Those toward the outside become phloem. More become xylem than phloem.

Removing bark or applying a tourniquet on the feeder stem stops the flow of sugars (food) down it. Therefore these sugars pile up at the discontinuity. Similarly, auxin piles up where there is a discontinuity in the cambium - this results in an increased rate of cell division in the cambium above the discontinuity.

Now with these facts about how trees work, @Adair M, please try again to explain why 'you can start to weaken the feeder portion of the branch'. The technique is correct (an established experimental fact). Your attempt to explain the technique works and/or what it does is _____!

 

[Adair M]

Water and nutrients are drawn through the xylem (wood) by the foliage. Sugars made by photosynthesis (food) are conducted downward (away from the foliage toward the roots) in the phloem or inner bark. Auxin produced by the growth tip/buds and foliage is move down the tree from one cambium cell to the next.

The cambium causes radial growth. Cambium cells divide. Those toward the inside become xylem. Those toward the outside become phloem. More become xylem than phloem.

Removing bark or applying a tourniquet on the feeder stem stops the flow of sugars (food) down it. Therefore these sugars pile up at the discontinuity. Similarly, auxin piles up where there is a discontinuity in the cambium - this results in an increased rate of cell division in the cambium above the discontinuity.

Now with these facts about how trees work, @Adair M, please try again to explain why 'you can start to weaken the feeder portion of the branch'. The technique is correct (an established experimental fact). Your attempt to explain the technique works and/or what it does is _____!

Ok...

Boiling your rant down to the essentials, you're saying that the techniques I describe work. Right?

But you don't like it when I say "force the graft to use the graft junction", or "weaken the feeder", right?

Oso, most of the people who post here, or read these posts are not biologists. You start talking about auxins, phloem, xylem, discontinuity if cambium, etc, and you lose them. Yeah, that was boring stuff they sat thru in high school, but they DON'T CARE about why it works. They just want to know what to do to make their grafts work.

Now, I've stood up in front of people and tried to explain about the flow of auxin snd how decandling stops the flow, and taking away the suppressor allows the adventitious buds to grow... And I can tell you, they start getting fidelity, they stop paying attention... They just don't care! Oh, a few do. But I've stopped trying to explain it scientifically, I tell it in layman's terms.

It's good that you can supply the details on all this. I don't mind at all. Just don't put me down for telling people a good technique in a way they can understand.

 

[0soyoung]

Just don't put me down for telling people a good technique in a way they can understand.

I agree with that so long as you aren't inventing misleading non-sense doing so.

But you don't like it when I say "force the graft to use the graft junction", or "weaken the feeder", right?

No, that is simple and isn't misleading. But it isn't what you said. You said

This will force the tree to use the graft to feed the scion.

Consider saying something like '.. it forces a faster/stronger fusion of the graft to the tree ...'. Simple and biologically correct - really.

 

[Adair M]

Oso, if it makes you happy, you are welcome to come on to my threads and/or posts and explain the science. I can't think like you. I just put it in words that us ordinary people understand.

As a matter of fact, I try to dumb it down so that the focus is on the technique.

Does the average bonsai hobbiest care wether it's the phloem or xylem carrying the auxins? No. They just want their grafts to take. In my years of teaching bonsai, no one has ever even said "phloem"or "xylem". Shoot, they barely get cambium!

You know that Elton John song "Rocketman"? There's a line in there that goes something like "And all the science I don't understand. It's just my job 5 days a week..."

Most of us are like that.

 

[Adair M]

Oso,

It's kinda funny...Expressed in "Big Bang Theory" terms, I playing Howard. The Engineer. You're playing Sheldon the Theoritical Physicist.

We're BOTH nurds!!!

Lol!!!

 

[0soyoung]

I try to dumb it down so that the focus is on the technique.

Devil is in the details.

Oso,

It's kinda funny...Expressed in "Big Bang Theory" terms, I playing Howard. The Engineer. You're playing Sheldon the Theoritical Physicist.

We're BOTH nurds!!!

Lol!!!

A couple of years ago I was talking with Bob Bower over lunch after a hike through the local forest lands. I brought up the subject of 'The Big Bang Theory' and he says, 'You know, there really are people like that.' Well - duh.

 

[Dav4]

Oso,

It's kinda funny...Expressed in "Big Bang Theory" terms, I playing Howard. The Engineer. You're playing Sheldon the Theoritical Physicist.

We're BOTH nurds!!!

Lol!!!

 

[pitchpine]

Hey Adair,

I'm sorry, I don't think I explained my question clearly enough. Here's a much better picture :

As you can see, it's a small side shoot of the donor branch that I'm trying to graft. So for right now, it's not the portion of the donor branch between its original juncture with the trunk and the graft site I'm wondering how to treat, but the larger portion of it beyond the offshoot.

I know I want to to maximize the energy going into the grafted portion of the donor branch, so my first inclination was to prune back to the blue line. However, since the donor branch is coming from a location on the trunk above the graft, would it maybe be better to let the whole branch grow out for a bit longer (and thus theoretically strengthen the graft union by maximizing the thickening of the trunk beyond the graft site) ?

Thanks!
Laura

It takes at least a year for it to take, so be patient.

You can start to weaken the feeder portion of the branch. Two ways: 1) slice off a section of the bark and cambium below and above on the section of twig feeding the graft. This will force the tree to use the graft to feed the scion, not the old stem. 2) loop a piece of wire around the feeder stem. Twist it tight with pliers. As if to strangle it. Tight enough to just barely begin to cut in. Again, this restricts the glow of nutrients, and makes the scion use the graft junction.

Good luck!

 

[Adair M]

Decandle the 1 branch, don't decandle the 2 branch.

 

[pitchpine]

Thanks! Will do.

Decandle the 1 branch, don't decandle the 2 branch.