Thrips? Mites?

[swamprad]

I’ve got a problem in my greenhouse.

This is a small growing grammatophyllum. The leaves look awful and have this sticky stuff on them too. Top and bottom of leaf is shown.

Next are some suspicious looking areas on a Cattleya and and Epi flower.



Next are some suspicious areas on some flowers. And some sunken spots on Dendrobiums leaves. That is not scale.

Have I got thrips? Mites? Haven’t dealt with this before.

 

[big923cattleya]

Whatever you decide to do, do not treat Dendrobiums with anything containing sulfur. It could kill them.
Yes, on the red Reed stem Epidendrum flowers, I am 99% sure that the damage is from thrips. They are famous for sucking the life out of buds and flowers. I have had them make the buds go brown practically overnight on Vanda, Cattleya and other orchids. Good one day, crispy and brown the next.
Mites, false spider mites and just plain old mites, are hard to see. They thrive with exploding population numbers in low humidity levels. You will need a ‘miticide’ to take care of those. Just follow directions on the label.

 

[Morja]

Insecticidal soaps often say they kill both thrips and mites on contact (check the bottle), so it may be worth treating your collection frequently (1-2x a week) with that for several weeks. Thrips are really a pain, because they lay their eggs in plant tissue and will keep coming back until you get all of them as they hatch, since most things only kill them on contact (and even those things should be rotated since they tend to build up resistance). One of the users here finally got a heavy duty thrips-specific systemic insecticide that she will get a packet of to whoever may need it (if she still has some!) and it takes one or two doses to kill them off.
As far as being sure of which it is, I'm not horribly experienced but just had some thrips myself and your issues definitely look suspicious. The dimples on the underside of some of the leaves make me think of mites too, with my untrained eye, though I suppose it could all be thrips. Can you inspect with a magnifying glass? Those flowers should have some thrips in the crevices if they're there.
Ever tested for viruses? Some of that damage looks suspicious too... I hope others with more experience weigh in