AusBonsai

A couple of months ago I had a visit from a newbie & as we had been talking about the subject decided to show him the basics of how to perform an airlayer. The subject is a Casuarina cunninghamiana that started life as a self sown seedling in one of my pots, it was transplanted & grown in pots for about 3yrs before I decided to put it in the ground, that was 4yrs ago & it hasnt looked back. If not for shortening in a storm 2yrs ago it would be bigger still. My target section is the damaged area plus a bit more, its about 4-5" dia with plenty of branches all round. I forgot to take pics at the time but used a saw to cut 2 rings around the trunk about 2" apart, peeled the bark away & bagged it up with plenty of sphagnum. No rooting hormones were used (I never do!). Not the best timing but its finally starting to root and they are hard to miss! Given its size, I will be waiting till I have a really full bag of roots before cutting it off. One thing I am wondering.... When the branches & trunk are reduced to start regrowing it will leave the tree completely bare, will a bag full of roots be enough to push new growth... OR Would it be better to shorten everything right back a couple of weeks before removing the layer so it can feed off the mother tree to get the process kick started

Hi Matt, I usually prune back hard just before severing from the mother tree, so that the new roots don't have as much foliage to supply water to. Otherwise it can dehydrate badly or die.

Thanks Hack.

I always cut them back before seperating but this is the first time I will end up with a bare stump, I am just not sure the new root system will be enough to push good backbudding.

Hi matta.
I was asking this very question last year and have found with last years experence (20 layers) that lots of different species of layers have no trouble powering on when removed with no folage . i removed a 3 inch casuarina layer over 4 weeks ago that had no folage and less roots than your pic and it has started pushing lots of new growth . abviously it would be better to have some folage on there to help but wont hurt.
also my casurina has 2 large wounds and now has buds surrounding every bit of each wound ( no die back) remindes me of the way a chinese elm responds to heavy pruning. I think you would have no worries removing that layer now.

good luck

Thanks for sharing your experience Paulneill. It can be a great way to build a collection of nice trees quickly. It only has 2 lots of active root so far so I might let it go a while to get some more roots.

2 weeks on, little development of the existing roots & no new ones, somethings going on... A look in the bag reveals the answer, the whole cut area has healed over! So instead of stuff around off it came... After cleaning away the loose sphagnum & removing the excess trunk its not a great sight. The drainage holes were meshed & wire threaded thru to tie the tree into the pot. A piece of paver was the perfect height to keep the stump off the bottom of the pot. The tree now firmly tied in , I tested it by picking the whole lot up by the trunk:tu: Filled up & topped off with a layer of sphagnum to help maintain moisture, a good drink of seasol & its off to recovery. At present the stump stands 50cm cut to cut and approx 10cm dia. I have an idea in my head for it but we will wait & see if it pulls thru or not first.

Wow... i didn't realise Casuarinas could be chopped back to a stump!? Backbudding on these things is good I assume? haha

-Mo

Mo, In general Casuarina cunninghamiana will back bud strongly after this sort of chop.

Hey Matt,

I will be REALLY surprised if that lives, just based on my experience.

But then again, you do crazy stuff all the time and regularly come up with super impressive results too. Either way I will be watching with interest. Good stuff!

Good luck,
Joel

Hey Joel,

I wont be surprised if it lives OR dies, I have done some pretty major work on this species in the past and results varied...I am curious why you feel it wont pull thru...

I am seriously thinking of shortening the trunk remaining in the garden so another layer is quite possible. If I do I will make the cut much deeper & also put a ring of wire around it to help prevent the healing I got with this one.

Updates as & when there is something to report.

Matt

Ps Crazy does... crazy is...

Hi matta

I'm curious as to how you knew there were only 2 active roots when they were surrounded in moss . Did the moss fall away or did you remove it ? Whatever roots are the are very delicate and should not be disturbed . Air layers should be potted up and tied into position . But I'm sure I'm telling u how to suck eggs.
I don't fancy it's chances By looking at it but who knows it might rally .
Good luck let us know how it goes!

Paul,
It was clear looking thru the plastic that only 2 zones of root had developed, as such the remaining moss simply fell away. When roots grow, in general they head away from the trunk to the outer edges so its fairly easy to see development if checked regularly, one reason I prefer transparent plastic over black for my layers, sunlight has no negative effect on new roots, air is the pruner.
Matt

MattA wrote:Hey Joel,

I wont be surprised if it lives OR dies, I have done some pretty major work on this species in the past and results varied...I am curious why you feel it wont pull thru...

I'm confident you can cut them back that hard - sure. I'm surprised you can get one to survive with so few roots though. Certainly a collected one with that many roots wouldn't pull through (or I'm just crap with after care). But the combination of being severed with so few roots and all those cuts potentially drying out the trunk.... I have never seen it done to this severity so I don't really have anything to back it up. It just seems wrong to me without evidence, which means I have made an assumption that you are testing which is why I really enjoy your posts!

Joel

Only had 1 sucess collection so far. and that had almost all the roots with it as well. All the other not survived and some with heaps of fine roots too

Joel, just being lazy, I should have recut the bridged area & rebagged it.... We will all know soon enough... had a look at the remains this morning & another layer is definitely in the offing. With a deeper cut & better season heres hoping