Unpot Newly Potted Phal Because of One Rotten Root?

[RandomGemini]

I'm a beginner too Ginger. I got my first orchid a year ago. I just read a lot. It stops me from messing with my orchids too much.

[james mickelso]

And here's why. GThe rot you see on the root is just the velamen (spongy material covering the root) and the plant is healthy enough to ward off any further development of the rot. Let the plant fight it's own battle on this one. The velamen will get soft abnd rotten looking without actually being diseased. opportunistic bACTERIA WILL FEED ON THE SOFT MATERIAL AND BREAK IT DOWN WHICH IS NATURAL AND SHOULDN'T HARM THE REST OF THE PLANT.

[Ray]

And, as I've stated many times... Whenever you repot a plant, even if it's into the very same potting medium, the roots that grew in the old medium are not optimized for the new stuff. We expect them to eventually fail and be replaced by new roots that ARE optimized for that environment.

[james mickelso]

Then I have a question Ray. What mechanism in repotting and using new media deteriorates the old roots? Unless something stresses the plants root system, it should continue to grow regardless. As far as I know there is no symbiotic growth of bacteria that is disrupted by repotting. I have repotted many orchids where there has been not even a hiccup in the root system. I have posted pics of rescue phals repeatedly that show continued growth of the root system and that included repotting into different media. But...you are correct if you are referring to old roots on old pseudobulbs that don't need the old roots anyway and they just stop growing and their moisture and nutrients are sent forward to the new roots growing on new growth anyway. Cattleya's and oncidium's roots on old pbulbs usually die back within a season or at most two while new pbulbs grow new roots. So I am very interested in what mechanism is at work deteriorating the roots on an orchid when it is repotted. Maybe I can learn something I didn't know before.