Air layering phyllstachys Dulcis

[stevelau1911]

Around 3-4 months ago I decided to put a pot over a rising shoot barely out of the ground (not a whip shoot) on phyllostachys dulcis. As it rose, I added soil a bit at a time and as expected it rooted out in the pot despite being a regular culm. I severed it from the mother plant approximately 6 weeks ago however it seemed like it was time to up-pot it into a 3 gallon size from 1.5 gallon.

Despite this plant being all culm with absolutely no rhizome attachment, I found that a rhizome was still forming out of the bottom likely from a dormant branch node which still had the ability to turn into a rhizome. It looks like this form of propagation can be pretty useful when a bamboo does not put out any whip shoots however I would have to try it on other species and succeed to call it a viable propagation technique. Has anyone else tried this before on a regular culm?

Here are the pictures.


It definitely looks like a rhizome.


I up-potted it to a 3 gallon put to allow it to establish in the next 2 months.

[bamboothew]

Very interesting experiment, Steve! I have been wondering about such things. Perhaps in the same way that a rhizome exposed to light can become a culm, a culm part never exposed to light can become a rhizome? I dunno, but that sure looks like a rhizome in that picture to me!

[zxylene]

I was just going to post a comment on your thread "raising the soil temp" about how much I love your experiments and your way of thinking and then you post this one about rhizomes from culms anyhow thanks for your posts they are always an interested read.

[bamboothew]

And I as well, what zxylene said

[stevelau1911]

Bamboo has been the most fascinating plant I've ever grown so I've been trying all kinds of experiments from propagations, graftings, winter protection set ups, different environments in order to find out more about them. The reason I tried this experiment is because I have observed rhizome generation from the base of a vivax culm which led me to believe that the bottom nodes of a culm that were never exposed to light can become viable rhizome buds, and this experiment seems to have reinforced that idea.

Most shoots produced on a mature grove are usually true shoots, not whips so that's why I believe this can can be effective. The only drawback is that the bottom drainage hole may need to be cut open a little more since most rising shoots even if they are the smallest shoots on the grove are fatter than the tiny drainage holes at the bottom of a nursery pot, and it can take a bit of effort to sever the connection once the division is well rooted. I'm not sure if topping or dwarfing the division is really necessary since this one never showed transplant shock when I severed it, but it was done for the purpose of ensuring success in this given experiment.

[bamboothew]

Steve, I am just wondering for clarity, was this the only dulcis shoot you tried this on or did you try more than one and only this one worked?

I have a spare nigra grove that I planted solely for experimental purposes, so I'll try your technique on a couple of nigra shoots in the spring and let you know how they turned out.

[stevelau1911]

This was the only one I've tried and I can already see that this technique could have been improved very easily. As you can tell, it was taken a few nodes up from the rhizome neck so many of this culm's roots came out under the pot, creating a weaker division.

If I would have moved away the dirt around the shoot and tried to get the entire shoot in, including the rhizome neck, I think there would be a much bigger root ball along with more rhizomes coming out of the base. I never knew it was this easy to get divisions until now.

[meadowyck]

I have read that for a more tasty bamboo shoot to cover it a keep the light off of it.

Your method is very interesting and a lot less work....

Please keep us informed.

Jan

[needmore]

It looks like that rhizome is coming off of a short section of rhizome where you can sort of see a line in the middle of the dirt, no?

[stevelau1911]

If you blow up the first image, you'll be able to see that those are just regular roots. There was was never any rhizome sections included in the division.

[Alan_L]

I'd really love to see all of the soil washed off so we can see exactly what's going on. Any chance of that happening Steve?

[stevelau1911]

I don't like to wash soil away, but I can get it and show a clearer picture of the attachment to the culm once I get a chance. Washing soil away tends to cause leaf curl and quite a bit of set back which I would not like to have especially since the growing season is almost over. My dulcis doesn't produce that many culms so I can't afford to lose this division.

I will definitely repeat this once I see some true shoots rise again which hasn't happened since June, but I am suspecting it will only work on the species that tend to generate air roots on the lower nodes unless I put the pot all the way down to the shoot neck. If this works 90% plus, it may be useful for large single culm divisions.

[Alan_L]

I've washed soil from several divisions, and I've never seen it causing the problems you list. Yes, if you use a power washer you're going to be breaking loads of feeder roots, but if your soil is as loose as it looks, you can dunk it in a bucket of water for a few minutes, swish it around a little, and most of the soil should fall off.

Isn't it more important to verify exactly what this technique has resulted in, rather than having one viable division? I think there's only a very slight chance of causing any "harm" to the plant, but there is much information to gain.

[foxd]

I can understand Steve's reluctance to clear away the soil to see what is happening, I have several plants I would like to know what is going on under the soil, but have put off cleaning off the roots to see what is happening. What I have decided to do in such cases is to look at them later when I feel the plants would not suffer from the experience. I would suggest Steve wait until he feels confortable looking and take lots of pictures.

[stevelau1911]

Looks like there's more curiosity than I thought about air layering so I'll get into the details a little more with some more pictures.

There are a total of 4 rhizomes coming out of the culm from the 2nd to last node to the 5th to last node, all originating directly from the dormant branch buds, and with the node right above the last rhizome, there are branches from there on out. This was with no mistake a true culm given that there are no excessive internodes at the bottom, the shoot came up completely straight with the appearance of a true shoot in early May, and I tried to get as much of the shoot as possible into the drainage hole, nearly down to the shoot neck without breaking off the horn. I was afraid that digging into the soil to put the nursery pot over could have aborted the shoot.

Here's a view of the 4th rhizome from the bottom. It's the smallest and the 3rd one has so many roots around it so that it's impossible to get a good picture.


Here's a bottom picture with rhizome 1 on the left and rhizome 2 on the right.


Rhizome 2 growing straight out from the culm.
.

Here's a close up of rhizome 2.


Rhizome 1: You can tell that the rhizomes are in descending size from the bottom up.