Brown pitts on paph. leaves

[orchidman22]

My lady slipper orchid has recently developed large brown spots on its leaves. I'm not sure when they began to develop, but I noticed them shortly before going on vacation. Since first noticing them (2 weeks ago), they don't appear to have gotten worse. It's hard to tell, because I don't know how long they (brown spots) took to grow to the current size. In any event, the orchid is growing a new shoot that doesn't appear to have any brown spots, so I'm not sure if whatever trauma the plants must have experienced has subsided, or if these spots are an indication of something worse to come.

Would you please look at the pictures I've attached to this post, and let me know if you have any ideas on what may have caused the condition and how/if I should address the condition? The first picture shows the brown spots as they appear on top of the leaves. The second shows the brown spots as they appear under the leaves. The third picture shows the new healthy-looking shoot. The fourth picture shows the name of the orchid. The fifth picture shows the location where the orchid resides in my apartment (on a windowsill that faces a small balcony to the south west).

Thank you!

[Blueszz]

Maybe it's mechanical damage. It reminds me on the browning around bite marks on a Paph. leaf (maudiae type), caused by one of my cats

It doesn't look like damage caused by insects (at least not to me) but you might want to give the plant an extra health check.

I hope others chime in.

Nicole

[orchidman22]

Hmmm... We do have a cat, but he's never attacked any of our plants before. There doesn't appear to be any holes in the leaves.

[Blueszz]

No, no holes visable, but I do see sort of cell collapse. That is why I thought it could be damage caused by insects, but (I'm not sure) cold or heat could cause this too.

Bump... others please help us! :-)

[DebsC]

Looks like it might be something of a bacterial infection. Maybe water stood on the leaves too long? Possibly a sunburned spot? Is it spreading?

[billc]

I had similar brown spotting on a strap leaved paph about 2 yrs ago. Not sure if a viral or bacterial infection. The advice I got was to treat the infected area with 70% rubbing alcohol on the upper and lower portion of the infected leaf. I soaked a Q-tip with the alcohol and rubbed onto the spots and it seemed to have stopped the spread of the spots. I did this several times over the course of a month.

Bill

[orchidman22]

The spots don't appear to be spreading at this point, but as I mentioned, it's hard to tell, because I'm not sure how long it took for them to grow to their current size. My wife usually waters the plants, but she doesn't always pay attention to their condition. I believe she assumed these leaves were dieing from old age. She's better at routine maintenance, while I'm better at recognizing when there is a problem.

It's possible that water stood on the leaves for too long. I didn't realize this could be an issue, since its kept indoors. I'm not sure about the sunburn. We've always kept this orchid in the same location. We've had it about 1 to 1 and 1/2 years now.

[orchidman22]

The rubbing alcohol suggestion is an interesting, yet concerning proposition. Does the alcohol have the potential to kill healthy tissue around the spots?

By the way, the spots I posted are from one leaf. There are about three or four leaves that have similar markings to varying degrees.

[Beverly]

I have a paph with mottled leaves like yours, that have the same spots, but worse. I think I caused it by leaving it in to bright a window, under a dripping plant. I have moved it to a lower light window and it seems fine now.
Beverly

[orchidman22]

Sounds like water and/or light is probably the culprit. I'll try to address these issues and monitor the situation.

Thanks so much for all of your suggestions!