Red spots with halo on oncidium twinkle.

[BrassavolaStars]

Hello all,

While I was spraying my plants for mites, I noticed that this oncidium has some disturbing spots on it.

I know that’s it’s normal for oncidiums to have spots but these don’t look typical.

The spots are mostly pale on the top of the leafs but have red dots on the underside of the spots. Is this a fungus? It reminds me of the photos I’ve seen of cercospora. Should I treat it with cleary’s? Hopefully it’s not viral.

[philiplowrey]

looks fungal to me

[BrassavolaStars]

Originally Posted by philiplowrey

looks fungal to me

That’s what it looks like to me also.

[SouthPark]

Originally Posted by BrassavolaStars

Is this a fungus?

It could be. Where is this plant grown? Is it supplied with good air circulation at pretty much all times?

Just as a precaution, you could try clearys 3336/thiomyl or mancozeb. Isolate the plant too - just in case.

Avoid having the plant in still air environments - especially in a bathroom-restroom combination.

[BrassavolaStars]

Hi all,

The plant was hung near the roof of my greenhouse. It was also under the roof vent. It is one of the plants that is further away from the fan. Since it’s right under the roof vent (which is closed), I thought it would be okay to be a bit further from the fan. That part of the greenhouse is also around 72f/22c.

While I’m not sure that the circulation in the greenhouse is ideal, there is always a 5000w shop heater fan running 24/7.

I am wondering if it could be an issue with dripping water since it was right under the roof vent and it’s been rainy lately? That being said, I’ve never seen the vents leak.

I brought it into a bathroom for quarantine and better light for a picture. It seems like that may be a bad place for it though.

I will definitely drench it in the fungicide though as it seems to most likely be a fungus. As much as I don’t like fungi, they are still preferable to viruses.