Weird discoloration on cattleya leaf
 

I have noticed a weird kind of mottling of dark and bright green and yellow on my Lc. Fire Dance Patricia. :( Is this normal or a sign of something bad? It only affects the pictured leaf...I was wondering if it had anything to do with the amount of sunlight the plant is getting and whether more sun is reaching some areas of the plant than others? But I have also seen mottling be indicative of a possible virus or other nasty so I want to be sure. Ideas? Thanks!

Is it concave or convex ?

concave, you've got a disease.

Convex it's edema. You water too much for the activity of the plant given the temperature. See Images of Edema on Orchids for examples.
For edema it's a cultural problem, water less.

Is this on the oldest pbulb/leaf? It looks like normal aging to me.

Brooke

I don't follow what you mean by concave or convex... the shape of the leaf? Or the coloration of the leaf? :/

I checked just now, it is neither convex nor concave. The leaf is the same level all over, even where the color is different.

I've had Cattleyas with similar symptoms in past. For me it has happened when light levels were drastically changed and/or lacking magnesium.

Here is a link to a some good information:

http://www.staugorchidsociety.org/PD...ySueBottom.pdf

Thank you :) The light changes would make sense (if that's what it is) - they're in a west window and we've lost an incredible amount of sunlight what seems like very quickly to me (though probably longer for them).

In case it is due to a magnesium deficiency, a low dose of epsom salt would help.