Dendrobium with shrivelled cane

[NatalieS]

First off, I apologise for not posting a photo as I know this would be more helpful, but unfortunately the battery in my camera is dead and needs to be replaced so I'm just going to try describing the situation as best as I can.

I have a Dendrobium Queen Emma which I bought about two years ago. After it dropped its flowers initially, the leaves on the oldest cane started to yellow and drop off. They did drop off in the order of oldest to newest leaf on the old cane and I had read that this was normal for some Dendrobiums and to leave the old cane as new growths can start from it (which is what I did). After a rest period in winter, new growths started to appear at the top of each of the canes, including the old one, but only one of the growths on one of the newer canes matured and flowered.

After a decently long flowering period, the flowers dropped once the weather started to get cooler and at this stage the old cane started to really shrivel and darken in colour. I would really like to cut it off as it doesn't look very good, but I'm not sure where, or if, I should cut it. If I do cut it, should I apply a little sulphur to stop any kind of rot from developing on the open cut? I haven't done any 'major surgery' on any of my orchids and am a little hesitant!

Just as an aside, this same Dendrobium has developed a keiki. It has about eight, large, healthy roots developed and two leaves with a third on the way - is it time to separate it from mommy and pot it up?

Thanks,
Natalie

[King_of_orchid_growing:)]

I don't recommend cutting the older cane(s) off. They are providing necessary energy for the keikis (the little growths all up and down along the canes).

[NatalieS]

This is why a picture would be so much more helpful! Believe me I would not be contemplating cutting anything off if there were keikis on it.

I will explain a bit more:

There are three canes, two of which are absolutely fine i.e. nice, fleshy, bright green canes and bright green leaves. It is on one of these canes that a single keiki is growing, and the other cane is the one that has just dropped its flowers.

However, the third, and oldest, cane no longer has any leaves and has recently become extremely shrivelled and discoloured (like a dark browny-yellow colour). The discolouring is what is worrying me the most.

This dend. is by far the most particular of the orchids that I grow - it hates any changes in temp or light. It is my gut feeling that something has happened to this plant (maybe a sudden drop in temp) which has caused the cane to shrivel and discolour. I wanted to know if anyone else had seen something like this before and if they'd ever removed a cane. Believe me, this cane looks dead as a door-nail and my biggest fear is some kind of viral/fungal infection that might spread (although I know they normally spread fast and the cane on this plant has been like this for over a month).

If you don't think it's doing any harm though, I will leave it be!

Thank you!

[silken]

Normally I leave old GREEN shrivelled canes on my nobile dendrobiums. But if it is turning yellow and brown, then I would say it is no longer providing energy to the rest of the plant and could be starting to rot. It may just be dying a natural death too. I would cut it just above the potting media level. Leave it a bit taller so water isn't always getting into the cut. And a dab of sulfur on the cut is a good idea.

I will add, you should always use a sterile knife so as not to introduce disease into the new cut.

[NatalieS]

Thank you for the advice - I think I will remove the cane as you described.