I have also observed roots from above ground nodes branching into deep mulch, aggressivlely, in a transplanted Ph. aurea. These were fine roots, not rhizomes.

Makes me wonder if Phyllostachys actually can be propagated from culm cuttings?

hmm, I have not disturbed that mulch in months. I'll check later if any rhizomes have also budded from the lower nodes. The transplant of last December has been successful as I can see, across a 60-foot-wide creek, that 10 or so new culms have come up and leaved out well in the last couple months

It's all food for the bamboo so I'd be surprised if it hindered shooting or growth in any way.

Kurt, remember me telling you last summer to be prepared for topkill? It's the nature of the beast, not the mulch. The large divisions generally do not have the rhizome/root mass capacity to provide moisture to the large/tall culms during that first winter, when the real cold happens. I do not believe that I have ever had a large division NOT topkill in year 1.

The rhizomes will move up into the mulch zone if they prefer the conditions there during the growing season, and that is why it's really important to mulch deeply LATE in the year - Halloween, or Thanksgiving, after rhizome growth has ceased, then you can really bury the new rhizomes.

Jerry Burton in Ohio exclusively uses the free mulch from the company that maintains the utility easements. I used about 10 truckloads from them myself one year and this stuff is mainly twigs that aren't very chewed up. It did break down in about 2 years though but I don't think I'll mulch with it again. Jerry's source must be grinding it up smaller, he likes it because he can easily remove LONG sections of rhizome and he does all of his starts via rhizome cuttings so this works well for him. I don't really like growing from rhizome cuttings, I always end up with some but I can't stand how slow they are.

kstanwick-
Last year I dug some big divisions and wanted to "let them rest" before I planted them, so I laid them down in the shade, buried the rootballs in a pile of medium grind bark/mulch, and watered the pile regularly. After two months there were new roots emerging from the pile and the rootballs were shooting. I figure, if they did well in this situation, that your topkill was not the result of over-mulching.

OK guys thanks for the reminder. You know what it is for me? I'm sad i had such nice size culms when i dug the arrow. and now i'm left with what looks like weeds coming up. Brad you are correct on the bigger woods chips. If i come across them i'll use them but mixed with other OM. I guess is just a waiting game. waiting out the first full season can be so long..... lol.

Kurt