Question

sick leave   Hi, Wayne!
Thank you in advance, for trying to help me.
Orchid is two stem, with large white flowers.
Very nice specimen.
When I bought it, I have noticed small yellowish  and groovy spot on one of the leaves. It was less obvious then, than now.Still got the plant.
Love large white flowers and two stems.
Over time, it became more yellow and groovy.
Is it fungus,or other disease??
Plant is still blooming, and otherwise, very good looking and healthy.
I was thinking to cut out the damaged leave, but not sure, if the whole plant need treatment? How correctly to cut the leaf, it is first leaf from the top crown.

Thank you

Answer
Thank you Natalia for your question and the picture. This looks like mesophyll collapse in this leaf.  I would use a sterile cutting tool such as a fresh razor blade and remove the leaf.  We need to prevent potential spread to the crown of the plant.  Remember, when it is done flowering, to repot the plant in fresh fir-bark based orchid potting mix.  At that time you can check root health when you unpot prior to repotting.  Be sure not to use moss of any kind and don't let the pot stand in water. Grow the plant a bit drier until you can repot. When you water, do it early in the day so any water on plant tissue has dried by nightfall.  Do not use ice cubes to water your plant--a technic advocated by some mass marketers.  When you are ready to repot, you may have additional questions so feel free to ask.