mites! Oh no...
 

Hey all, I picked up a Dendrobium lanyaiae from Andy's Orchids recently at the SF Orchids in the Park expo (which was fantastic, btw), but just returned from a week's vacation to a full on infestation on the plant. Looks like mites of some kind, full on life-cycle - adults with black wings, and more translucent ones which look like younger insects. There's a bit of webbing on the stick, and the mites are fully in and around the medium - it's a stick mounted plant. Plant still seems healthy, but I'm freaked out - it was in my tank with my other mounted plants, but looks like nothing has spread so far.

There's a few holes on the stick, and I'm thinking that the mites arrived inside those, as they seem fully infested! Would neem oil work on these jerks, or do I need something stronger? Thank you for any advice!

-Tristan

Neem oil should work but you have to be diligent and treat repeatedly per the product's recommendation.
Also, increase the humidity.

Mites are related to spiders. They're arachnids not insects. Mites don't have wings.

If they're black and have wings, they might be fungus gnats.

Translucent worm-like caterpillars with black heads are a clear sign of fungus gnat larvae.

The webbing though might be associated with mites, idk. Although, it could also be from spiders as well.

Re-Fungus Gnats - that makes sense, as the bugs seem to be clustering more on the stick than on the plant. I wonder, could my humidity in the tank be the problem? It's fairly high - I wonder if the fungus gnats are all about the stick decay, rather than the plant!

Thank you Philip and Eyebabe, I appreciate the suggestions.
Gonna treat with Neem and let the stick dry out. Plant is a den. anyway, so it should be ok with that.

-Tristan

Adults and larvae prefer to eat fungus, but they're not above eating roots, tubers, or tuberoids. They like soft rhizomes too.

The larvae are the worst. Adults, not quite as bad.

Might get a few sun dew and butter wort Carnivorous Plants.
Don't know if this has anything to do with not having fungus gnats but I use the mosquito dunks in the rain water that is stored . :)

Agree , doesn't sound like mites ,they don't have wings and are very difficult to spot with the naked eye unless you know what effect/damage they do to the leaves.

Neem oil will not kill fungus gnat larvae as they are not eating the plant.
It will however kill the flying adult insects.
If you want to kill the larva, soak some mosquito bits in your water before giving it to your plants and that will do the trick.
Also, you can find out what is rotting and dispose of it....

Algae lice?
 

So, the guys at Andy's suggested they may be 'algae lice', which don't harm the plant. This fits in that the plant is in a humid tank, but I'm looking around and can't find anything at all on that bug - apparently they won't bother the plant, but will eat Algae off the stick.

Anyone heard of these?

-Tristan

You mean springtails?

They look like lice. But they're not lice.

Springtails are now no longer considered insects. They are hexapods.