Black areas on Onc leafs

[Old Root]

Noticed this AM. Wasn't present yesterday. I'm a newb and no clue to what is happening. Thanks for your help!

Top of leaf



Underside



Another underside pic



Currently potted like this



---------- Post Merged at 11:09 AM ----------

Apologies to all. I just realized that I posted this in the wrong thread.

[chemist]

I think you post in right thread but also could be posted in other.
I dont have any onc so can't say exactly wht it is.
How long do you have this plant?
It could be mechanical damages or could be fungus infection. If it last one you might want to get some systematic fungicides to treat your plant.
Im sure more experienced growers will comment soon.

[78Terp]

I use Physan on my Oncidiums with spots. In many cases, for Oncidium Alliance orchids, the spotting is only an aesthetic thing. Looks somewhat unsightly but doesn't kill the plant.

Others may have a different viewpoint.

This is my Onc Sharry Baby. Nuff said!