pasquale wrote:Interesting Fly. I look forward to seeing if you have managed to create a lignotuber (or just a large scar). If you have I figure that means you caused some root development (proteoid roots) that regressed but the potential for root growth remains. I'm not a plant biologist but I guess that would mean you have promoted growth of undifferentiated cells (or de-differentiated). I can't recall if you use rooting hormone.
Gday Pasquale!
I'm pretty positive that I have managed to create something more than scar tissue: when you look back through older photos of the layering process, you will find definite evidence of the beginnings of roots. Unfortunately, due to my lack of proper care, these have dried out and receded.
I did not use root hormone on this tree, and I don't know if it would be of much use, as the River Reds seem (generally) very willing to root by themselves.
Dom124 wrote:Air-Layering is on the " i want to do more " list.
but with threads like this it makes you want to attempt more trees... thanx mate
Gday Dom!
Properly executed (unlike this example), air-layering is a great way of obtaining large and/or established material very cheaply. Let us know how you go!
Creeping Dragon wrote:Have you thought about adding a physical border to stop bridging? Or is it bridging to keep itself alive?
Sorry, pardon my ignorance.... If we were to physically stop it bridging, say with a metal wall that ran around the bottom cut, what would that achieve, anything?
Gday CD!
As I understand it, the 'bridging' is the tree's way of attempting to heal itself in order to save the portion above the layer site. Assuming that the layer throws sufficient roots early enough, these roots will begin to support upper growth almost independently of the base. In such cases it is my observation (assumption?) that when a layer roots well (thus taking some of the strain off the lower trunk), the tree is already well on the way to becoming 2 trees, and as such the layer site is not treated by the tree as a wound, and bridging is minimized.
In regards to your 'physical border': it might be of some use, but on a tree which puts on girth quickly (such as a young River Red) I would be concerned that the tree could become strangulated as its diameter exceeds that of the solid barrier, thus stopping the upward flow of nutrients/water to the layer site. I have read about the 'tourniquet' method of layering which involves tightly wrapping a wire about the trunk and twisting the ends until the wire bites into the bark. The theory here is that the tree will grow into the wire, and gradually the saw flow to the roots will be stopped at the wire, causing roots to shoot. It sounds kinda like what you are suggesting, but one major difference is that the cambium layer is protected by the thickness of the bark, and should not be strangled as the trunk expands.
In short, I guess I'm saying that I wouldn't bother. In future, I'll be using the same method with the exception that I will try to ensure better conditions for the layer to take (IE: I'll make sure to water properly
).
Thanks all!
Fly.
From memory, my exact words were:
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