White Hard Spot on Dendrobium Leaf

[c123anderson]

Hi, again, everyone. I'm sorry to take everyone's time with endless questions. I have another "identify this"-type question.

One of my mealybug-attacked plants was my dendrobium Miva Abracadabra. I've been watching this one, as it came to me with some areas on it that were concerning. No obvious pests or disease -- just damage.

I've noticed a leaf with a white, hard spot on it. It doesn't seem to change, yet it's got a black ring around it, like it's damaged the leaf. I've included a picture.

Today I examined this white spot, and took a pair of tweezers to try to examine/remove it. It kind of flaked off, and the leaf has a hole it in where I had used the tweezers.

What is this white spot?

I've observed something similar on my vanilla, on one leaf. Nothing spreading. No change. Upon examination, nothing obvious. Treatment with a little isopropyl alcohol does nothing.

[Roberta]

I think it is old damage that dried up. Nothing to worry about. Keep the questions coming¡

[c123anderson]

Thank you, Roberta!