WoW!! I wish I knew... Love the stripes though.
CJ

Looks like Phragmites mixed in with the Pleioblastus. Maybe???

Thuja-
I don't know much about Phragmites, but I did a Google search and some of the leaf forms look suspiciously like that. I do see that Phragmites can get really tall. Are there short species as well? At this point, my rogue growth is only about a foot high.

If this were a rose, I would say that the root stock is different from the primary form. If that were the case, then there should be a graft scar somewhere near the base of the plant. I have never heard of this with bamboo, but I also have never had a variegated bamboo.

I would remove the unwanted growth and try propagating from part of the plant that you know is variegated. The puropose would be to eventually get rhizomes that you know are true to type. The easiest way to do this in your situation would probably be ground layering.

kudzu - my first impression too, was that it is not bamboo. Have you given it a good tug to see if it pulls out of the ground easily?

But I also have had a similar experience. 4 years ago I dug a bunch of Pl. Viridistriatus from a friends patch of it. I now have a green bamboo also coming up with it and I was wondering if this too may have been a reversion to a green form? As with yours, the leaf structure is somewhat different. Mine looks like a Pygmaeus cultivar. I went back to the original grove which is many years old and I see only a couple of these green guys, no where near the ratio that I have. My friend has since passed away and I have no one to ask if 2 species were planted together either intentionally or accidently.

I'll follow up with Adam Turtle and see if he knows of either of our species behaving like this. My gut feeling is that it is 2 different bamboos that got mixed together somehow.

One more piece of info. When I was out this morning I was feeling the leaves. The striated bamboo leaves are smooth, while the rogue stuff has sandpapery edges and is also raspy on one side. I'm believing it's either another bamboo or even a non-bamboo plant. I intend to dig it and try to separate the two. It's interesting because the non-striated one is coming up not only around my original one, but through the center. I'll report back if I figure out anything when I dig it up later this week. Thanks for the ideas...

I believe the striped is Pleioblastus fortunei, if it is a dwarf bamboo. (About 4 FT max height. And the new growth according to how the leaves grow from the Steam is a Pleioblastus Distichus, which is another dwarf Bamboo that grow with the branching formation shown in your picture. However do not hold me to that, I have a Pleioblastus fortunei that the new shoots are all green then change to striped latter. Also, I think the Pleioblastus Distichus has a rough edge as you described. Let me know if this help.

The green leaved plant is not a bamboo. It doesn't have the leaf stipes that are a distinguishing feature of bamboo. It is probably some grass that germinated from a stray seed in the soil.

>>The green leaved plant is not a bamboo. It doesn't have the leaf stipes that are a distinguishing feature of bamboo. It is probably some grass that germinated from a stray seed in the soil.

I too support this theory. Pull some of it up and look at the roots.

I don't know of any dwarf forms of Phragmites. Normally this grows 12-18' or so tall. There is a variegated form that is smaller. It has rhizomes which look very much like bamboo. Here's a pic of its ligule for comparison.
{{gwi:421879}}
You probably wouldn't see as much setae since these seem to shed fairly quickly. This is a photograph of a new culm.

Could be a type grass (besides bamboos) as there are thousands and they look similar. This maybe a reversion of ribbon grass that nurseries have. If the above ground part dies and resprouts in the spring then thats what it is.

Here is a link that might be useful: Ribbon Grass

You guys were right! I dug around the perimeter and found a bunch of impressive roots, but they were independent of the bamboo. It was just an opportunistic grass enjoying the congenial growing conditions. I uprooted all this stuff without disturbing the bamboo too badly and it looks a lot better.

I am glad you found the answer to your mystery, Kudzu9. And a happy ending too. But just for my own education, is it true that bamboo leaves do not sheath the canes like the last picture that Kudzu showed? And that if this is observed, it is most likely a grass?

It really looks like you got a "bonus" grass stuck into the pot that your 'boo was in. The roots must have gotten woven together as they grew in the container. Can you extricate the "alien" invader?

Cady-
That was the situation. It came up so nicely all around the original planting that I thought it was just the bamboo spreading out. I had to significantly dig around and under the rootball to get this stowaway removed, piece-by-piece. It was not only on the perimeter of the bamboo, but coming up the middle of the planting. Whatever it was, I have to respect it: more aggressive than a runner!