Question
My husband purchased a cattleya orchid, Lc. Mari's Magic,
at an orchid society silent auction five days ago. There are
8 pseudobulbs, 3 have had the leave cut off before we got it. There is one new healthy looking shoot. Three of the five leaves left look relatively "healthy." The two others have definite black oval areas, the worst being 1 1/2" long x 1/3 " wide about 1" from pseudobulb. It does not go through the other side of the leaf. On the underside of the leaf at the tip, the entire area is black dotted about 1 1/2" in length. The other "sick" leaf has an area about 1"x1/2" with pronounced black dots. I have isolated this plant and hung it outside in the shade of a beech tree. I am
considering cutting off the two bad leaves to the pseudobulbs, taking the plant out of it's pot and soaking it in a physan 20 solution. I am not sure if this could be a fungus, or a virus, but I would like to try to save this plant if possible. Do you think my plan is worth trying?
If soaking is a good idea, what strength of physan 20 and for how long should I do this?
Do you have any other ideas of things I could try?
Thanks!

Answer
Bernadette, I like your plan.  As you know, it is difficult to diagnose a disease strictly from a written description.  My first inclination is to consider this as sunburn.  However, the physan soak is a good idea just in case it is a fungus.  It does not sound like a virus.  I suggest that before you do the physan drench you cut off the leaves below the blackened areas and dry off the plant before repotting.  Orchid societies often have experienced members who can offer advice so glad you have some contact with the local society.