Arakawa airlayer location

[Kanorin]

I picked up this Arakawa JM about 3 weeks ago and planted it in the ground. Since it's grafted, I'm planning to airlayer it.


I was thinking about trying it here (orange-stripe marks below) because
1) There is an interesting single or double trunk line from that spot
2) It's my first attempt at an airlayer and it's near the top of the tree, so if I screw it up, I can try a lower spot next year.

Thoughts? Words of encouragement?

 

[Brian Van Fleet]

That’s looks like an awkward spot to me. A bit too high for twin trunk, and the left side has a whorl of 4 branches emerging from the same spot, which will create a bulge or pruning scars when you realize you need to remove 2-3 of them. I’d go for this spot if you want a twin trunk. It will leave something alive below for later and you’ll start with a larger, usable trunk.

 

[Canada Bonsai]

also a possibility: arakawa is easily propagated via cuttings!

this tree will easily give you 10-15 cutting that, by the end of this growing season, won’t be too far behind your air layer in terms of trunk thickness anyways!

as an aside, if your landscape specimen is grafted, you may want to air layer it so that it’s base also develops the beautiful bark! (Bill Valavanis has 2 spectacular specimens!)

 

[Kanorin]

OK, so I took @Brian Van Fleet 's advice and went for a twin trunk layer at his suggested spot. I decided to try a tupperware variation for how to house the future roots (I think I saw another thread that did something similar).
Here goes at my first air layer attempt.
Here's the cut



Progress...


Did I remove enough?


Also, thanks for the confirmation that they can be propagated by cuttings @Canada Bonsai - Did you use any root hormone when you've done it? I didn't have any luck with cuttings of a different JM variety last year, but it was also my first time trying it. I did take a few cuttings from this arakawa 2 weeks ago and another 3 today. Fingers crossed.

 

[Kanorin]

And here is the tupperware with custom twin-trunk holes. The branch below it actually holds it in place nicely.



I decided that some aluminum foil over the seam might help prevent evaporation as well as prevent the sun-exposed side from baking.

But I can still peek in the back to look for roots...

 

[Canada Bonsai]

@Kanorin nice work

It looks like excess water will drain from your container if it is on the correct angle. I would make sure that it either holds that correct angle, or that it has a drainage hole regardless of its angle.

I would have chopped that sphagnum moss much more and mixed it (about 50-50) with some kind of substrate (akadama, or any ordinary bonsai mix that you happen to have around). If you only use loose sphagnum moss like you've done, you will end up with roots like the shishigashira air layer in the image. They are still salvageable, but not ideal. And in bonsai, we are looking for ideal in almost every situation.

Last summer i did a test:
Air layers with just bonsai substrate mix
Air layers with sphagnum/substrate mix.
Air layers with just sphagnum.

It was not possible to differentiate between air layers with just bonsai substrate and those with sphagnum/substrate mix (mind you, i am around to water them every day if needed). Air layers with just sphagnum (although I did chop it), were significantly worse (as in the photo).

Did you use any root hormone when you've done it?

I use rooting hormone on all Acer Palmatum air layers and cuttings, but I only do this because it is what I was taught, i've seen it work for my teacher, and it works for me! I know that @0soyoung , who is much more qualified to speak on the topic than I am, has mentioned on this forum that rooting hormone may not be necessary.

I did take a few cuttings from this arakawa 2 weeks ago and another 3 today. Fingers crossed.

Arakwa cuttings work marvellously! The first trick with any Acer Palmatum cutting is really perfecting the timing in your backyard. For me, it is the 1st and 2nd week of May. For other others, it is as early as April or as late as June. If your timing is off, there is little that you can do afterwards to keep them alive and strong. There's a window of a about 10 days with any given tree branch shoot, in my experience. I will recommend to you the same book that I recommend to everyone. It's the gold standard. There are all sorts of devices, gadgets and tricks nowadays, but what is written in that book is a timeless procedure that always works if you do it right!

 

[Brian Van Fleet]

OK, so I took @Brian Van Fleet 's advice and went for a twin trunk layer at his suggested spot. I decided to try a tupperware variation for how to house the future roots (I think I saw another thread that did something similar).
Here goes at my first air layer attempt.
Did I remove enough?

That’s lower than I recommended; I drew the top cut just below the split so you’d have 2 trunks at the ground level, like this. Yours will have some trunk, then a split. It may be a bit awkward at the base, but over time it may work out fine. This is my air-layer arakawa, notice how I positioned it so the swelling base flows nicely directly into 2 trunks, with no single “stalk” first:

 

[Kanorin]

Thanks for the replies. Maybe I'll open up the tupperware lid and add in some pumice or akadama.

This was my first air layer ever, so I guess I didn't get it to the exact spot. Didn't know how far up from the top of the cut the tree throws roots - I guess it's pretty much right at the top of the cut. Learning experience!
Love your Arakawa, Brian - your thread was part of my inspiration to pick up this tree when I saw it in the nursery. Thanks again!

 

[Captain.Bonsai]

Thanks for the replies. Maybe I'll open up the tupperware lid and add in some pumice or akadama.

This was my first air layer ever, so I guess I didn't get it to the exact spot. Didn't know how far up from the top of the cut the tree throws roots - I guess it's pretty much right at the top of the cut. Learning experience!
Love your Arakawa, Brian - your thread was part of my inspiration to pick up this tree when I saw it in the nursery. Thanks again!

If you’re going to change the substrate you might as well cut that bark ring up a little higher.

 

[Brian Van Fleet]

Thanks for the replies. Maybe I'll open up the tupperware lid and add in some pumice or akadama.

This was my first air layer ever, so I guess I didn't get it to the exact spot. Didn't know how far up from the top of the cut the tree throws roots - I guess it's pretty much right at the top of the cut. Learning experience!
Love your Arakawa, Brian - your thread was part of my inspiration to pick up this tree when I saw it in the nursery. Thanks again!

It will root at the top cut; ideally all the way around it!

 

[Kanorin]

Update: It's been 25 days since the cut. Since this was my first air layer attempt on any tree, I'm worried that maybe I didn't scrape away all of the cambium and was healing rather than throwing roots. I didn't see any roots visible from the sides of the container, so I decided to take a look at it on a wet rainy day.
Side 1

Side 2

Is that white undulating ridge the beginnings of new root tissue? Or is it callusing or some type of fungus?

 

[ajm55555]

From my experience, the white is a sign of growth and doesn't have anything to do with the airlayer. The callus seems fine, just be patient.

 

[Kanorin]

Update: Around 45 days post girdle. Still leaving the layer attached - I can't see any large roots from the side or base of the tupperware, but I haven't opened the lid and dug around in there. I'll give it some more time.

I noticed something interesting: The leaves above the girdle have taken on some deep red coloration at the tips, which could be a sign that they aren't receiving much moisture. The leaves below the girdle are a vibrant green.


Actually, I feel like the leaves above the girdle were even more red a week ago and seem to have shifted back toward the green side within the last few days. Maybe it's a sign that the roots are starting to form at the girdle...or maybe I'm just watering the tree more.

When I do remove the layer (not going to do it until I see roots or at least a few more weeks), is it a good idea to put it in a mostly shady spot with just ~1-2 hours of morning sunlight. And then gradually increase the light exposure? Right now it's in about 6-7 hours of sun.

 

[Kanorin]

Another interesting thing that I noticed is that performing the girdle induced a flush of new growth down on the trunk below the girdle after about 3-4 weeks. This makes sense since the auxins released from the leaves above the girdle travel through the cambium layer and stop at the girdle, helping to induce new root formation.

But the leaves are weird on this flush of growth!


Not sure if it's due to
a) hotter weather and more intense sun in June vs. April - maybe the tender young leaves got scorched?
b) some kind of fungus or insect?
c) the plant having been put into the ground this year
d) other

 

[Brian Van Fleet]

Mine get that way too this time of year, especially on those long extensions. Not a problem.

 

[BrianBay9]

I wish I had the ability to put some trees like this in the ground. I'd like to try developing the structure of a bonsai on limbs of the still in-ground tree, then air layer it as the last step, after the structure is established. Leaving it on the mother tree during development should speed everything up. You've got a great opportunity to try that on a different portion of your tree.

 

[Kanorin]

First attempt didn’t work (maybe stayed too wet or I checked it too often). Neither did the second try (got impatient and separated with too few roots. But third time is a charm!