Cercidiphyllum japonicum Air-layering or cuttings

[Timbo]

Just wondering if anyone has had any luck with Katsura tree air-layering or hardwood cuttings. I have 2 high pencil thick branches on my 4+ year old seedling in the ground I have to get rid of. It's the only one i have and i'd like to propagate more of them if possible. No info online, which normally means not much success. I tried 10 semi hardwood cuttings last springs and couldn't get them to shoot out roots.

 

[0soyoung]

I have a "Red Fox' that I layered, but it took a couple of seasons and the explant has been weak on its own roots. It seems to do fine during the growing season, but a branch will drop leaves early and then is verifiably dead the following spring. Per this trend, it will be dead this coming spring after 3 years on its own.

The mother tree is grafted onto standard standard katsura root stock and was a potted ball&burlap-ed field grown tree. I've been trying to 'clean up' the roots for the last two years. The varietal has been weakly growing and root growth has been weak. It will be left alone this next year, hoping it will gain some strength.

My net conclusion is that katsura are not the most vigorous root growers, certainly weak rooting, compared to maples but not quite as tender as a pine. One might say they don't like having their roots messed with, I suppose.

I have tried to root cuttings from root stock suckers to no avail. IOW, I suspect it might be classed as 'difficult to root'.

 

[Timbo]

I have a "Red Fox' that I layered, but it took a couple of seasons and the explant has been weak on its own roots. It seems to do fine during the growing season, but a branch will drop leaves early and then is verifiably dead the following spring. Per this trend, it will be dead this coming spring after 3 years on its own.

The mother tree is grafted onto standard standard katsura root stock and was a potted ball&burlap-ed field grown tree. I've been trying to 'clean up' the roots for the last two years. The varietal has been weakly growing and root growth has been weak. It will be left alone this next year, hoping it will gain some strength.

My net conclusion is that katsura are not the most vigorous root growers, certainly weak rooting, compared to maples but not quite as tender as a pine. One might say they don't like having their roots messed with, I suppose.

I have tried to root cuttings from root stock suckers to no avail. IOW, I suspect it might be classed as 'difficult to root'.

I put it in the ground 2 1/2 years ago as a seedling, I root pruned it at the time pretty hard. I dunno what the roots look like because i'll have to check when i dig it up, but after the first year i got really good growth on it. It has really thickened up the truck this year.
You are on the high end of the hardiness range, do you think that has anything to do with the air layers/roots? From reading, they are suppose to have shallow roots.
Hmmm...If they take 2 seasons to air-layer i dunno if it's worth it for how fast they grow.
So hardwood cuttings are just a waste of time.
I was going to check the roots this year and if i cut any off obviously i don't think air-layering after root pruning is a good idea. I'm just going to cut off the top anyways. Decisions...decisions!
I like the trees, and they grow fast here. I will just try the seeds again this year no matter what i do with the mother plant. I am not aware of anyone selling them in the area or i would buy some seedlings here.
The only success i've read about is softwood cuttings in summer, but i seem to have low success on softwood cuttings overall.
Thanks for the response.

 

[Shibui]

I have occasionally had katsura cuttings root but strike rate was very low. So long ago I can't remember whether I used hardwood or summer softwood cuttings. Humidity is vital with summer cuttings so misting system would be required for good strike.

 

[0soyoung]

You are on the high end of the hardiness range, do you think that has anything to do with the air layers/roots? From reading, they are suppose to have shallow roots.
Hmmm...If they take 2 seasons to air-layer i dunno if it's worth it for how fast they grow.

I think summer heat may be part of my problem, or the lack of it. It rarely gets much above 70F here. Everything grows here, just slowly. I have difficulty with layers of acer palmatum "Shishigashira", for example, but people in hotter southern climates quite readily get layers to root within 6 weeks. Standard green acer palmatum, a.p. "Orange Dream", and a.p. "Shindeshojo" produce abundant adventitious roots, but the layers do take about 4.5 months.

Katsura appear to do well in my climate. There are a six or so 15-ft plus tall ones as landscape plantings scattered around the neighborhood within a few block from my house. The city of Dupont, WA (on the south side of Seattle) plants katsuras as street trees. There is a nursery 15 miles away from me that has a grove of 50 year old katsuras (I visit every fall to inhale their cotton candy, carmelized sugar aromas). So, it could be simply an issue with my treatment of the 'Red Fox (Rotfuchs)' cultivar. I started with a big tree and anticipated far more vigor, so it is hard for me to avoid thinking I've pushed it too hard. The layer, though ....

I equate 'shallow roots' stuff being about air - roots need oxygen to grow. Some species are more 'needy' than others. Both, my original grafted tree and my air layer are in several inches deep Turface MVP which has higher air filled porosity than any garden/yard soil that I know. So I think the stuff you've read about is in the context of landscape plantings and basically is a warning to not pile up soil/mulch under the tree. I don't think it relevant to bonsai culture.

 

[Timbo]

I like the 'Red Fox (Rotfuchs)' Color....I think i like the way the original grows though. TBH, i haven't even seen any surface roots in the ground. Anyways, we will see what happens, either way i need to get rid of the branches.
I haven't noticed the cotton candy smell yet, i read about it before, I only have 1 tree right now though.
In a month or so i will surface sow the seeds inside, hopefully i get a decent amount of germination.

 

[ThornBc]

I managed to propagate a hardwood cutting almost by chance, as I just stuck it in the ground with little care, while my more carefully selected green wood cuttings failed.

 

[rodeolthr]

My experience is that the Red Fox (Rotfuchs) cultivar is muuuuuuuuch slower growing than the species. Also, concerning roots, I have several seedlings given to me by friends when they yanked them out of their gardens. I pot them into regular nursery soil and within one season the trees have rooted into the ground under the pots. I give the roots a hard cutback when repotting and so far they don't seem to mind. More me, the roots have been very fine and traveling in all directions without massive anchor-type roots. It could just be how I'm growing them. I have no experience with cuttings on this species.