Tiny dots of sticky stuff, what is it?

[Dawn-oh]

Hi All,
I hope I can describe this strange thing going on with a few of my orchids which started with a Cymb. backbulb I was rooting, and on occassion, it turns up on different orchids. First off, even with a magnifying glass, there are no insects at all creating this residue that I can see. On the underside of a Cymb. leaf I felt some "honeydew" one day. Unfortunately I didn't catch it right away, because those areas started forming brown spots underneath. Then the top side of the leaves turned brown in spots as well. It looks exactly like leaf spot. The spots are not sunken or raised or mushy, they're just weird dark spots! I cleaned the leaves with diluted alcohol and occassionally use an insecticide just in case.

This turned up on the first set of new growth leaves from this backbulb a year ago....the second set of growths from the same backbulb looks fine, and I again noticed tiny dots of sticky stuff on the underside of those new leaves just today, but I caught those in time before that stuff killed any cells. Again, with a magnifying glass, I see no insects. What the heck is this stuff and where is it coming from? Has anyone ever had some weird viral disease in a plant that gives the symptoms of aphid honeydew?

I saw a teeny bit on the underside of a few other thicker leafed orchids, but I have been keeping such a close eye on them that I can clean the leaves before things get out of hand. This is bizzarre, any ideas or suggestions on prevention? I can't find anything like it in orchid disease/insect stuff I've read so far. It seems like an insect would be the culprit but I can't see any! As for putting that orchid in "solitary confinement", that's nearly impossible with 300 plants inside the house for the cold Minnesota winter because it needs to share the artificial lights.

Sorry this was so long, I appreciate the patience of those who took the time to read it tho, thank you!
Dawn-oh

[ang709]

Is it only on new growths? I get honeydew on the new growths of some of my orchids, but it is normal and doesn't hurt them. I've never had brown spots develop after.

[ischel1]

Aphids are often the culprit when you see honey dew on leaves. They leave it behind(excrement) and then a fungus grows on the honey dew, turning the leaf brown/black. Hope this helps.