stem rot/aborted roots?

[Calbears]

I just repotted this noid phalenopsis this weekend and after removing the dead/rotted roots I peeled back the old dry sheathing from the stem. As you can see from the picture, there are numerous black bumps on the stem. Are these an indication of stem rot or just root tips that aborted for whatever reason? Is removing the old sheath critical to ensure the new roots grow?

[shushu45]

I don't know really but I think it is where the roots came off the stem.

I would really love to find out myself.

[Joyorchid]

It looks like you have some good healthy roots and if it were me, I would not cut or trim anything else. What media are you going to use?

[jeremyinsf]

I think the question many of us are wondering though, is "why".

[Calbears]

It was growing in the Gublers coarse mix and recently had been losing leaves faster than they were growing. They were leathery and soft. In retrospect, I realize that it was way over potted and the clear container from repotme.com didn't drain well. I decided to try s/h with this phal as it's actively growing new roots. I had tried s/h once before with a phrag besseae and failed. I ignored the advice about timing the switch with new root growth and it was a slow miserable decline. So far this one is responding nicely. The leaves are firmer and less leathery after a couple of days in s/h.

[RosieC]

Those black bumps look like they are places where old roots have been removed, or sometimes I've seen them as places where roots started and then aborted.

[Calbears]

A few are where the old roots came off but most are perfectly spherical and were only visible after peeling off the dry remnants of old leaves which makes me think they're aborted roots. The black color however made me worry there was some fungus at work on the stem. I haven't seen much mention on these forums, but I'm curious what lengths experienced orchid growers go to remove the old dead material (sheath, where the leaf attaches to the stem on monopodials, etc.) from their plants or if they let them go au naturel.

[RosieC]

I've seen ones like this before, to be honest I think only on orchids which had been struggling but I know at least one of those I didn't do anything about it and the orchid is now fine. (Can't remember which the others were sorry, so not sure how they fared).