Another spot on a different leaf

Did you look it up on the AOS website? I certainly don't like the look of those black areas and I would cut them off to clean tissue.

I have had it happen to me but it didn't spread to other orchids. Its been a few years, but I remember it started with the pbulb turning black.

Could be wrong, I just remember cutting off the pbulbs until clean tissue. It does spread fast and you need to take action quickly.

Sure looks like it.

Good luck

Jane

Here is a link that might be useful: Black rot

I had black rot on a couple of plants years back and it spread to others Carts, which is why I pulled this one so quickly. I save 1 of 5 that got infected. Plus the one I saved has not completely bounced back yet. I am just going to let it go over trying to treat it. Darn. I really liked this one.

I snapped a picture on my way to work this morning.

Also to your question Jane. I looked on the AOS website and some others. There seems to be significant variation in how black rot can appear on different plants, locations, and stage of infection. I just wanted more eyes before I kept or disguarded the poor plant.

Pseudomonas cattleyae or Black rot. What Jane says - cut off to clean green.

It probably is but I've read that cal/mag deficiency can mimic black rot. I think it was an article in Orchids Magazine a while back.

I have had it happen to a few Catts over the years and found it spread quickly through the plant. It never spread to my other plants.

I became suspicious that it might be something else because it didn't spread. It certainly appeared to be black rot and wiped out the plants quickly.

In NY, my plants were cramped together due to space issues. I was surprised it didn't spread. When I had it happen again on another Catt, I decided to try and treat it quickly. I did salvage the plant, but it returned a few years later on the same plant.

Long story short, I took back bulbs from this Catt and grew them. Now in Florida, I'm finding those plants (4 backbulbs) continue to appear weak yet they did flower. I'm going to play with cal/mag to see if anything changes. If it doesn't, I'll toss them.

Must be 10 years I'm fooling around with this plant.

Jane

Thanks for the replies. I really doubt this is due to calcium/magnesium deficiencies. I have had my Catts on a calcium/magnesium program I while ago. The author of the recent AOS article on cal/mag deficiencies wrote an online article for the St. Augustine Orchids Society that prompted me to start supplementing. I have seen less extreme red leaves and experienced very few fungal issues since.

Since what I am seeing now is likely black rot, I tossed the plant. The spots were a lot more serve when I came home from work the afternoon. I don't want to black rot at the moment. Still a little sad about tossing it though.

Not only are the existing spot more severe, there are new spots.

Probably the best decision. I'm sorry..

Jane