I just recently got an Oncidium Gold Dust. It came with another purchase as an extra. I read online how to care for it, but after a few weeks it has developed a black spot on one of it's larger pseudobulbs. I just checked it again and it seems to be getting worse. What does this mean and how do I stop it? I don't have much knowledge on plant diseases and how to care for them. Does anyone have advice to give?

Thanks, Bethany Armstrong

Please insert photos of this orchids and leafes.

Bethany,
I'd cut off the psuedobulb and dust the cut with cinnamon or Rootone. Or, you can cut out the rot with sterile cutting tools and dust the wound with the same. In either case, keep the plant dry for a week or so till the cut dries out.

Sorry, I can't exactly add pictures online at the moment. Thank you for the advice. It seems to be doing just fine now. I should have taken into account that the plant had just gone through extremem weather and light changes, which can cause black marks to appear on some of the leaves. The marks are still there but the plant is healthy and is starting new leaves so I think I will leave them because they are on the biggest pseudobulb and I don't really want to take it out.