Tenuipalpus, False Spider or Phalaenopsis Mite control

[Welfkoondo]

Hello:
Does anyone have any experience identifying and treating for Flat/False Spider/Phalaenopsis mites? I am having a very tough time with my Oncidium Intergeneric Hybrids, Phalaenopsis and other orchids with severe yellow stippling on leaves. I tested for virus which were negative and tried many fungicides also negative. I also took samples to 3 professional orchidists who thought it was some sort of insect or mite issue. Even under a USB microscope I can't spot movement, legs, etc. so pretty sure not spider mites. All I see are tiny white specs. Most miticides only label for spider mites, not flat or broad mites, so struggling for an effective control whether chemical or biological......

[WhiteRabbit]

[Welfkoondo]

sorry - what does that mean?

[WhiteRabbit]

Originally Posted by Welfkoondo

sorry - what does that mean?

A 'bump' is just when someone is leaving a comment in a thread to 'bump' it up within the forum list and "today's new posts" list - usually done to hopefully get some helpful replies to a topic.

Sorry I can't help with your question.

[bethmarie]

I had Tenuipalpus on a Phalaenopsis last year, and they spread, of course. I ended up using Tetrasan and another, I think Floramite, on my whole collection. It wiped them out, but I did end up losing the Phal that started the whole outbreak.

[WilECoyote]

I had a phal schilleriana which had brevipalpus a year or so ago, when I bought it. There were no visible mites on the leaves, but the new leaves were scarred, and yellowed and fell early. Inspection of the leaves didnt show anything and i thought maybe the growing conditions werent right. Eventually I discovered mites and eggs lurking under the remains of the leaf sheath at the base of the plant. They are very difficult to see, you need bright light and at least a x10 hand lens. By the time I found them there were occasional mites on the leaf underside too. I sprayed with a contact insecticide based on sunflower oil, really drenching the crown, 3 times at 3 week intervals to catch any emerging mites, and I peeled away all the dead leaf sheaths to ensure the little blighters didnt have anywhere to hide.


This seems to have done the trick as I have not seen any live mites or eggs, and the leaves are growing fine with no scarring. It has just produced its first spike.

[Welfkoondo]

Thanks to BethMarie and Wilecoyote: it's good to know that Tetrasan works on them as I have some and also where to look for them!