Too Late to Air Layer?

[symbiotic1]

I'm wondering if it's too late in the year to try to start an air layer? I'm in the Los Angeles area so fall weather is very mild - heck it was 90 degrees yesterday still - and the deciduous trees have only started changing color and loosing leaves. I also don't have to worry about freezing temps as even the coldest winter nights in January/February rarely dip below the 40s.

Would an air layer work then at this time of year in my climate zone even if the trees I would try are going into some level of dormancy? I'm looking to try on a birch, crape myrtle and japanese maple all growing in the yard, and a bald cypress and wisteria I have growing as eventual bonsai in 10/15gallon pots.

 

[Poink88]

Just wait for spring. W/o leaves you most likely won't grow any roots anyway.

 

[Cadillactaste]

I would think with it in a somewhat dormant state...it would not be trying to push any new growth...I would be afraid of possibly weakening the tree itself. But again is only my thought...no facts to back up my thought process. I would say...there is a reason many hold off for a tree to be pushing growth before air layering. Weather it's success rates or what have you... ? ...

 

[bonsaibp]

I'd do all of them in March here.

 

[Bonsai Nut]

Yes, it is too late. Best time to start an air-layer is in the Spring, when the tree is strongest and pushing the most growth. With some trees you might even be able to start an air-layer and separate the tree in one growing season. So wait until Feb/Mar (which is when I start to see my trees pushing spring growth here in the OC)

EDIT / Bob beat me by two minutes I was typing while he posted

 

[Dav4]

Has anyone out on the west coast actually started an air layer in the fall? I'm thinking this would be a neat experiment to undertake if the answer is no. My thoughts are that, from an energy standpoint, trees are loaded with it as they enter dormancy, and the time of year is amenable to root growth, and drought/heat stress is at a minimum. My trees and perennials that over wintered in my garage in MA would always grow a lot of roots over the winter under the mulch before they froze...4 to 6 inches out of the pot drainage holes. Anyway, if I lived in LA or San Fran, I'd try it on not so special stock and see what happens.

 

[barrosinc]

this tree in the video looks dormant... and not in late spring
https://www.youtube.com/watch?v=CREGA3jxGJE

why is it done like this??

 

[Poink88]

this tree in the video looks dormant... and not in late spring
https://www.youtube.com/watch?v=CREGA3jxGJE

why is it done like this??

Did you watch it? Around 30 secs in...he talked about timing and it is spring when video was done.

 

[0soyoung]

this tree in the video looks dormant... and not in late spring
https://www.youtube.com/watch?v=CREGA3jxGJE

why is it done like this??

In this case it was when G. had time on his hands to make a video. Plus, there's nothing to get in the way of being able to clearly see what he's doing to the tree.

One can cut the girdle or apply a wire tourniquette anytime of the year, but just like people said repeatedly in this thread already, nothing will happen until after the foliage has hardened in spring.

The basic physiology is that the leafs produce sugars (photosynthates) and auxin. These are transported down the tree, toward the roots, in the phloem which has been disrupted at the tourniquette or top of the girdle (depending on which method you have chosen) stopping this flow. The accumulations of auxin and sugars causes some cambial cells to become roots.

As far as the part of the tree below the girdle/tourniquette is concerned, it is just like the branch got pruned (or trunk got chopped) at the time the girdle/tourniquette was installed.

 

[michaelj]

Has anyone out on the west coast actually started an air layer in the fall? I'm thinking this would be a neat experiment to undertake if the answer is no.

I did. It was a waste of time in one instance and a complete failure in another. The juniper sat around all winter doing nothing. Fortunately, they did not die, but I had another air layer, same species, that I began during the first February heat wave, and when I separated the layers later that summer, the one that began in fall had fewer roots, by far, than the one I did just as spring was approaching. I also tried it with Japanese maples, and they failed. Never again. I have some material I'm really looking forward to layering, but not gonna do it until Febuary or March.

 

[Poink88]

I did. It was a waste of time in one instance and a complete failure in another. The juniper sat around all winter doing nothing. Fortunately, they did not die, but I had another air layer, same species, that I began during the first February heat wave, and when I separated the layers later that summer, the one that began in fall had fewer roots, by far, than the one I did just as spring was approaching. I also tried it with Japanese maples, and they failed. Never again. I have some material I'm really looking forward to layering, but not gonna do it until Febuary or March.

As mentioned by 0soyoung, the tree need leaves to produce "food/building blocks" to force roots. I actually airlayer AFTER the new leaves hardened in spring.

 

[Dav4]

I did. It was a waste of time in one instance and a complete failure in another. The juniper sat around all winter doing nothing. Fortunately, they did not die, but I had another air layer, same species, that I began during the first February heat wave, and when I separated the layers later that summer, the one that began in fall had fewer roots, by far, than the one I did just as spring was approaching. I also tried it with Japanese maples, and they failed. Never again. I have some material I'm really looking forward to layering, but not gonna do it until Febuary or March.

Thanks for the post. I've always wondered about the potential for fall air layering in mild climates, and now I know that spring is still best.

 

[symbiotic1]

Thanks everyone for the informative responses and discussion! Not as many trees go dormant here because the weather is so mild so I didn't know if perhaps there was a chance, but it sounds like it's not worth it.

The explanations make total sense though, and michealj's experience proves the point. Maybe the wound partially healed over or the juniper decided to limit the energy it sent down that branch because of the wound the following spring so it had less scale/needle growth and thus less root growth.

I'll wait till spring then!