Difficulty and impact of approach vs. thread grafting?

[badatusernames]

I'm probably going to be attempting some of my first grafting this year, and I was curious to open this can of worms, if in fact it is a can of worms at all.

In terms of impact to the tree, is approach vs. thread grafting preferred from a horticultural perspective? Or are they generally the same impact to the tree?

In terms of difficulty level, do you find approach or thread grafting more difficult?

In terms of style, is one or the other more preferred, or is it simply a matter of which method works best at the time?

 

[Dav4]

Neither one should have a significant impact on the healthy of the tree if performed properly. A thread graft involves drilling through a trunk/branch, but the majority of the wood involved is dead and merely structural, with two small wounds to the bark/cambium. An approach graft involves creating a slightly larger groove through the bark into the cambium. When done properly, the damage to the bark with both techniques is minimal. With that being said, a successful thread graft will almost always look better then an approach graft. Ultimately, it's up to the stylist to decide which technique will provide the best outcome, and I'll employ both on the same tree in some instances.

 

[sorce]

For structural purposes I believe the order goes...

Find material that doesn't need grafts.
Make triple sure you need to graft if you think you need to.
Try harder to not have to.
Thread Graft.
Approach Graft.

Sorce

 

[badatusernames]

For structural purposes I believe the order goes...

Find material that doesn't need grafts.
Make triple sure you need to graft if you think you need to.
Try harder to not have to.
Thread Graft.
Approach Graft.

Sorce

Hah, that makes sense. I have a hunch it may make sense for the Japanese maple I posted a thread for, but I did also get that tree with an eye towards learning and to try new things with. I suppose if I fail and ruin it I can always go the longer route and chop in this instance.

 

[leatherback]

Thread grafting has a MUCH bigger impact on the plant. Most of the trunk is NOT dead but serves for water transport and/or storage. The areas above and below a threadgraft in the trunk die off, over large part of the trunk.

 

[Dav4]

Thread grafting has a MUCH bigger impact on the plant. Most of the trunk is NOT dead but serves for water transport and/or storage. The areas above and below a threadgraft in the trunk die off, over large part of the trunk.

I'll respectfully disagree with your assertion that thread grafts have that adverse an impact on the trunk of the subject. This tree had at least 7-8 thread grafts created last spring and there is no evidence at all that the trunk above or below the grafts have been compromised at all. How could the wounds callus and heal successfully if such an insult as you describe was inflicted on it? For bonsai purposes, it's not a big deal at all.

 

[leatherback]

For bonsai purposes, it's not a big deal at all.

Maybe not. The question was not whether it was an issue. The question was, which is a bigger insult. Hence my answer.

You cannot see what is happening in a trunk. The fusion of the branch with the trunk only happenas at the exit point. The inside never heals, that is lost to the tree. And the cells you cross are broken. These longitudinal cells are connected vertically, but not so much horizontally. Meaning that if you damage one, a number of cells up and down are left dysfunctional too. Consider a straw. Punch a hole in a straw and it looses its function. Same with the internal structure of the tree. Not a big deal in our lifetime. But a deal in the trees lifetime.

 

[AJL]

Maybe not. The question was not whether it was an issue. The question was, which is a bigger insult. Hence my answer.

You cannot see what is happening in a trunk. The fusion of the branch with the trunk only happenas at the exit point. The inside never heals, that is lost to the tree. And the cells you cross are broken. These longitudinal cells are connected vertically, but not so much horizontally. Meaning that if you damage one, a number of cells up and down are left dysfunctional too. Consider a straw. Punch a hole in a straw and it looses its function. Same with the internal structure of the tree. Not a big deal in our lifetime. But a deal in the trees lifetime.

You are missing the point that trees have the ability to heal by compartmentalising and growing around wounds, unlike drinking straws!
After all trees have evolved and survived millions of years of attacks by pests, diseases and physical wounding such as holes caused by Woodpeckers or broken limbs. Small puncture wounds caused by thread grafting should cause minimal damage to the xylem and phloem providing that the technique is carried out with care and tools used are clean and sharp,and the graft is well sealed. A healthy tree will easily grow and will heal around the points of entry and exit of the graft with no detectable impact on the lifespan of the average bonsai!

 

[leatherback]

You are missing the point that trees have the ability to heal by compartmentalising and growing around wounds, unlike drinking straws!

Nope.

You are missing the point that once the structure inside the trunk is broken, it is NOT fixed. It is permanent damage.

ith no detectable impact on the lifespan of the average bonsai!

As said:

Not a big deal in our lifetime.

The question was, which is a bigger insult

 

[Shibui]

I'm backing @Dav4 in this one. Use the technique that will give the desired results. It can be harder to get an approach graft that sticks out of the trunk at right angles or dipping downward a little but that can be done with thread graft.
No grafting technique is 100% successful even for experienced practitioners so be prepared for some learning and some failures along the way.

 

[JonW]

The first graft I ever did other than simply fusing ficus cuttings was a thread graft. It was much easier than I thought and the tree showed no signs of suffering whatsoever. It looks much more natural than an approach graft, which always seems to look like the branch is coming off at the wrong angle. I don't know the answer regarding which would have a bigger impact on the tree, but the size of the cut may not be too different, but an approach graft disturbs much more cambium - a thread graft only disrupts a small portion that heals as it fuses to the grafted branch. Just use the smallest drill bit that will allow the dormant buds to pass through.

 

[penumbra]

I am of the school that believes a thread graft is the best method all around.

 

[Dav4]

Fwiw, I've had better success with approach grafts on tridents while both techniques have been consistently successful with my palmatums The few thread grafts I've attempted on tridents never took while pretty much 90%+ of approach grafts are successful,.. don't know why, and use the same technique and aftercare with both species.