The science of air-layering

On your questions, I might add a caveat to the one about "moss or soil". I agree with the answer 100%, especially the part about it not providing anything to the tree, just a moist environment. But I think the choice of soil might be influenced by the more superficial issue of getting the roots out after the layer taking. Up to this point I have only used moss. But I have found it a pain to try and get it out of the roots so i can start working with other soils. I use the moss for the ease and flexibility of using plastic to quickly form a ouch around the moss. To use soil I would have to rig some pot system up and then fill with soil. Mine are all done on landscape trees and I have done 40 or more in one season, applied in one day. So ease is what I am after. But if you are working with just one or two layers and if its a nice potted tree the pros of the moss method might be overtaken by taking the time to setup some system where you can use soil which will easily come out of the roots and be closer to working as Bonsai. I have seen some discussions in favor of soils vs moss. I think I will be moving more that way because I think I will get better root results not having to work with the moss after cutting. And again GREAT TUTORIAL!
 
But I think the choice of soil might be influenced by the more superficial issue of getting the roots out after the layer taking. Up to this point I have only used moss. But I have found it a pain to try and get it out of the roots so i can start working with other soils.

Yes I agree completely. You can see in the photo of that Chinese elm I used sphagnum moss, but then I had to use tweezers to pull out a lot of it before I potted up the layer. If the layer had had delicate roots, I might have damaged some in the process.

Depending on how big your layers are, you might consider these:

rooter-pot-tree-500.jpg

I own a number of them of both sizes and use them on branches and it makes it a lot easier working with a soil mix. They come in two sizes and work up to a 1" caliper branch/trunk. The problem lies in the fact that they require a lot of space to fit and they really have to be aligned vertically - so a straight trunk or a long branch and they work perfectly. A ball of sphagnum you can pretty much use anywhere. - Oh and don't follow the directions on the rooter pots; they are bad.
 
Yes I agree completely. You can see in the photo of that Chinese elm I used sphagnum moss, but then I had to use tweezers to pull out a lot of it before I potted up the layer. If the layer had had delicate roots, I might have damaged some in the process.

Depending on how big your layers are, you might consider these:

View attachment 139872

I own a number of them of both sizes and use them on branches and it makes it a lot easier working with a soil mix. They come in two sizes and work up to a 1" caliper branch/trunk. The problem lies in the fact that they require a lot of space to fit and they really have to be aligned vertically - so a straight trunk or a long branch and they work perfectly. A ball of sphagnum you can pretty much use anywhere. - Oh and don't follow the directions on the rooter pots; they are bad.
Yes, LOL but my problem is doing so many it makes me feel like I am spending to much money! But yes as I really focus on pre Bonsai creation I think I will be more focused on using a kit like this or at least construct my own from spare plastic pots. Was already thinking of migrating a few to a more constructive approach this year. Wife want me to do ZERO! LOL. Not to mention I am cranking up my misting cutting system now so might postpone layers for a season. Goof thing about the cuttings is I can root prune and grow a great root system. Drawback yes, longtime to finished Bonsai. But for me I am looking to 10-15 years from now having material to work and play with in retirement, focus closer to smaller Bonsai, and another purpose is to just have my nice maple cultivars in nice easily appreciated forms.
 
Yes I agree completely. You can see in the photo of that Chinese elm I used sphagnum moss, but then I had to use tweezers to pull out a lot of it before I potted up the layer. If the layer had had delicate roots, I might have damaged some in the process.

Depending on how big your layers are, you might consider these:

View attachment 139872

I own a number of them of both sizes and use them on branches and it makes it a lot easier working with a soil mix. They come in two sizes and work up to a 1" caliper branch/trunk. The problem lies in the fact that they require a lot of space to fit and they really have to be aligned vertically - so a straight trunk or a long branch and they work perfectly. A ball of sphagnum you can pretty much use anywhere. - Oh and don't follow the directions on the rooter pots; they are bad.
Oh and let me know what you found as an issue with the directions and also the way you would use those pots. Thanks
 
Yes I agree completely. You can see in the photo of that Chinese elm I used sphagnum moss, but then I had to use tweezers to pull out a lot of it before I potted up the layer. If the layer had had delicate roots, I might have damaged some in the process.

Depending on how big your layers are, you might consider these:

View attachment 139872

I own a number of them of both sizes and use them on branches and it makes it a lot easier working with a soil mix. They come in two sizes and work up to a 1" caliper branch/trunk. The problem lies in the fact that they require a lot of space to fit and they really have to be aligned vertically - so a straight trunk or a long branch and they work perfectly. A ball of sphagnum you can pretty much use anywhere. - Oh and don't follow the directions on the rooter pots; they are bad.
Oh, I have been asked by the maple society to give some layering demos, but haven't felt like getting organized. But if you wouldn't mind, I would love to take you write up and maybe organize into a presentation in powerpoint, and/or a word doc or pdf. So let me know if it is ok to use your material.
 
I was trying to keep my comments extremely broad and to apply them specifically to auxin flow as it is related to air-layering :)
I expected different kind of answer! ;-)
Anyway, I don't think my question is directly related to this topic, but it is in some way! What do you think about the fact that some species has a lot of root suckers, such as pomegranate, flowering quince, crabapples, olive, etc..
Bonhe
 
I own a number of them of both sizes and use them on branches and it makes it a lot easier working with a soil mix. They come in two sizes and work up to a 1" caliper branch/trunk. The problem lies in the fact that they require a lot of space to fit and they really have to be aligned vertically - so a straight trunk or a long branch and they work perfectly. A ball of sphagnum you can pretty much use anywhere. - .
I used the string to pull up the slanting or horizontal branch into the vertical position!
Bonhe
 
Really nice explanation! You have inspired me. Eyeballing some experimental trees right now. Is there an ideal diameter?
 
Really nice explanation! You have inspired me. Eyeballing some experimental trees right now. Is there an ideal diameter?
Not really a ideal size. I would say one tip would be to avoid smaller branches if you have a larger choice available. Sizes of a quarter inch don't seem to work as well. Of course you would think the younger wood of a smaller branch might do better, but I think the larger ones have more action up and down form the leaves and roots. I guess I tend to find branches ~1 inch to be a nice size for energy and not being to large. Now if you are doing this on something in a pot that you can really get to, use a pot system for the layer, larger sizes are more manageable. Trying to wrap sphagnum moss around a 4~inch branch is a pain! LOL Different species might have some different ideals, all my layer have Japanese maples.
 
Q: After I separate the air-layer, should I prune the branches?
A: It is better to leave them unpruned, since the branch tips are providing auxin to continue to develop the new roots. If you need to protect the foliage until the new roots increase their capacity to provide adequate water, you can use a humidity tent over the tree. The sign that it is "safe" to prune the tree is when you see it start to pop new buds and push new growth.

Thank you for your time in writing this guide.

I wanted to ask about this part... I think a fairly common issue some have is that they air layer and the top section of the tree has too much foliage and so once it is separated, the new root system cannot keep up with all the foliage.
Wouldn't you say it is ok to prune the foliage an adequate amount, to help combat this? I understand your point but is it a severe enough problem to cause an issue?
Also sometimes larger air layers are done and it has a very large amount of tree on top and it is simply not feasible to keep it.

I by no means say this as a matter of fact, but I have pruned off large branches from a pyracantha which I air layered, which did fine. Not to say for a second that this means it works 100% of the time, every time, because that would be silly.
 
Really nice explanation! You have inspired me. Eyeballing some experimental trees right now. Is there an ideal diameter?
Not really a ideal size. I would say one tip would be to avoid smaller branches if you have a larger choice available. Sizes of a quarter inch don't seem to work as well. Of course you would think the younger wood of a smaller branch might do better, but I think the larger ones have more action up and down form the leaves and roots. I guess I tend to find branches ~1 inch to be a nice size for energy and not being to large. Now if you are doing this on something in a pot that you can really get to, use a pot system for the layer, larger sizes are more manageable. Trying to wrap sphagnum moss around a 4~inch branch is a pain! LOL Different species might have some different ideals, all my layer have Japanese maples.

Also the majority of the time, when it comes to trunks, bigger the better. Most of the time you want a thicker trunk, I'm sure not always though.

Although, I've never wanted a bigger trunk... I've never had any complaints.
(Sorry...:oops:)
 
I gave it a shot on this bougainville. Now we wait I guess...it fought back a bit. Maybe I should have tried the first go on a nonthorney species :(:(:(.
20170408_173701_001-2268x3024.jpg
 
This is also first I've heard of the foil thing.. and sun damaging the layer.
I'd wonder if anyone can attest to that trick more, nice thing to know.
 
I think a fairly common issue some have is that they air layer and the top section of the tree has too much foliage and so once it is separated, the new root system cannot keep up with all the foliage.
Wouldn't you say it is ok to prune the foliage an adequate amount, to help combat this?
This is a course of action if the layer was harvested too soon, but not a good one.

Don't be in a hurry to harvest an air layer! Fleshy roots that grow in sphagnum only need about 6 weeks to harden up in a bonsai substrate before the first freeze. In other words, don't harvest until 8 weeks before the average freeze date for your location.

If you know you don't have enough roots yet and/or the foliage starts to wilt within a day or two of harvest, I recommend putting it in a humidity tent. Spray occasionally with 2 tablespoons 3% hydrogen peroxide in a quart of water - nixes bacteria and fungus as well as mists the air inside the tent. Keep it out of direct sun while tented.

The principles are simple. Leaves make the stuff to grow roots.
Roots supply water that escapes though the leaves.
The higher the relative humidity around the leaves the lower the rate of water loss (which goes to zero as rH approaches 100%).

I assume I am not stealing Greg's thunder here.
 
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This is a course of action if the layer was harvested too soon, but not a good one.

Don't be in a hurry to harvest an air layer! Fleshy roots that grow in sphagnum only need about 6 weeks to harden up in a bonsai substrate before the first freeze. In other words, don't harvest until 8 weeks before the average freeze date for your location.

If you know you don't have enough roots yet and/or the foliage starts to wilt within a day or two of harvest, I recommend putting it in a humidity tent. Spray occasionally with 2 tablespoons 3% hydrogen peroxide in a quart of water - nixes bacteria and fungus as well as mists the air inside the tent. Keep it out of direct sun while tented.

The principles are simple. Leaves make the stuff to grow roots.
Roots supply water that escapes though the leaves.
The higher the relative humidity around the leaves the lower the rate of water loss (which goes to zero as rH approaches 100%).

I assume I am not stealing Greg's thunder here.

Alright, thank you. I understand the loss of water through leaves and humidity, science bit although I appreciate you telling me of course.

Simply put, reframe from removing foliage. Instead, let the air layered roots just keep growing until at appropriate size.
 
Simply put, reframe from removing foliage. Instead, let the air layered roots just keep growing until at appropriate size

Too simply.
Haven't we talked about this before?

Even so...

Balance!

There is a point where letting the roots go to long in a bag, or even a pot, will lead to tangled Ass roots that need to be cut off to look nice later anyway.

The widest possible colander may very well be the best thing to combat tangled roots on a layer.

A substrate that promotes fine feeders like Tesco/8822 fines will also help.

Of course with delicate roots, a guide for your saw his helpful.
https://www.bonsainut.com/threads/radialayer™-a-season-saver.17046/

Remember.

The best way to speed up time in bonsai is to prevent every and all flaw/failure.

Tangled Ass roots is a failure.

Again, I've only layered easy stuff.

But it always came with a previously thought out plan to remove everything unnecessary for the design upon removal of the layer.

Factor this stuff in properly balanced.

Faster Further Future Vision.

Removing a layer is no different than repotting IMO.

Repotting the host plant 3 years should give one an understanding of the balance required for an airlayer from it.

Better, would be rooting cuttings, digging saplings, and putting them thru extremes.....
Pot em with little roots, yank early rooted cuttings prune the roots and Pot em.
Bag some. Full sun some.....
Experiment.

Then the notion of a proper balance can be had earlier, within the same season even.

IMO.
You seeing those shitty roots on your maple is probly the best thing that could have happened to you with that tree.

You understand your low extreme.

Now next year, when you see beautiful, full, juicy, thick(not English thick), hard to rake thru roots, you'll know what headed to the other extreme looks like.

That is totally key to quick development.

Every year we have the opportunity to improve our trees.

There is a perfect place we can take them to each year.

Cut too much, development slows.
Cut too little, development slows.

Knowing your extremes makes finding the balance possible.

That's why killing trees is Friggin important!

That's why if you killed your elm or the layer, you'd still be better off!

And I mad commend you for being Ballsy!

Cheers!

Sorce
 
Too.....

As with potting.....

Where the moon is now is a good time.

I'm starting to repot tomorrow.

I may have one or 2 holdouts, who may not grow leaves till after the new moon.
They will be in full leaf by next waning moon, and repotted.

I would factor in the moon when removing late.

Remove during the last waning moon 8 weeks before first frost.

Sorce
 
Too.....

As with potting.....

Where the moon is now is a good time.

I'm starting to repot tomorrow.

I may have one or 2 holdouts, who may not grow leaves till after the new moon.
They will be in full leaf by next waning moon, and repotted.

I would factor in the moon when removing late.

Remove during the last waning moon 8 weeks before first frost.

Sorce

Thanks for info. I won't say much more cos I don't want to fill up Bonsai Nut's guide topic, with our talking.
I think I may do some air layering again this year, around now is a good time so I'll look around, and I'll bear in mind the moon phases for when I remove them later in the year.
I don't think my maples roots were too bad, it was the soil we found them in that was terrible and yeh you are completely right, the sad development on the maple due to that substrate showed very clearly. This year it's full steam ahead. :)
 
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