What is this..?

[paphioboy]

Guys n gals, I need help identifying this 'thing' which keeps appearing on the surfaces of all my orchid leaves. It looks greyish and dusty, but can be scrubbed off... As far as I remember, last year only my oncidium sphaecelatum was affected, but this year it has spread all the way to the orchid racks in the front.. :sob: Here's a pic of an affected leaf of Blc Sanyung Ruby:

TIA..

 

[NYEric]

Wow! How did my old camera get over there!?

 

[paphioboy]

Fer crying out loud, the pic's not that blur...

 

[Hera]

Looks like deposits in the water. How do you water? Hose, can, misting system, rain? Somewhere along the line the water is picking up debris. Mine look like that when I mist with a certain worm poo fertilizer that I use occasionally. I has a certain amount of dirt in it and it leaves a dustlike residue.

 

[NYEric]

The picture is so blurry that I ran to the eye doctor to get my vision checked! oke:

 

[paphioboy]

Hera, I always use the hose.. But I have not been feeding my plants for half a year, so it definitely cannot be fertiliser residues.. Maybe it is bad water quality..

 

[NYEric]

From what I can see, if it's not mold, it could be mealies! I hope not.

 

[cnycharles]

looks like deposits from water. also if your leaves have some deposits like honeydew on them the dust might gravitate towards them

 

[Clark]

new fan? more dust?

 

[biothanasis]

They look like dirty water drops remaining and drying on the leaves!! If you water and drops have remained on the leaves it is very easy to get this result if dust is on the air!

 

[KyushuCalanthe]

They look like dirty water drops remaining and drying on the leaves!! If you water and drops have remained on the leaves it is very easy to get this result if dust is on the air!

I agree. Each spring we get "the yellow sands" from Mongolia and northern China blowing over us. During those times everything outside looks like your photo. So, I think it is an issue of air quality, not water.

 

[SlipperFan]

It might be sooty mold that attaches to water drops and sugar secretions, especially when the weather is warm and humid, and with little air circulation. There's a name for it, but I can't think of it at this moment. It wipes off fairly easily with alcohol on a cotton ball.

 

[paphioboy]

Thanks, everyone.. Glad to know its not something serious. I was quite shocked when my dad sent me some pics showing most of my plants with this dirt on the leaves. Well, guess I have a lot of scrubbing to do when I get back next week.. Maybe the dust is from some construction site near where I live..

Dot, I don't think its sooty mould. I have a pic of sooty mould in one of my books and it is black and looks powdery, not in blotches like my pic.. Thanks anyway..

 

[SlipperFan]

Thanks, everyone.. Glad to know its not something serious. I was quite shocked when my dad sent me some pics showing most of my plants with this dirt on the leaves. Well, guess I have a lot of scrubbing to do when I get back next week.. Maybe the dust is from some construction site near where I live..

Dot, I don't think its sooty mould. I have a pic of sooty mould in one of my books and it is black and looks powdery, not in blotches like my pic.. Thanks anyway..

Perhaps not. But this looks a lot like what I've seen in the greenhouse where I volunteer, especially on thin-leaved plants.

 

[Jim Toomey]

Try spraying with a soapy solution first to see if that will help break up the "dirt" maybe you won't have to scrub the plants.
Jim

 

[paphioboy]

Ok thanks..

 

[NYEric]

I have some white mold on the wooden mounts of some pleuros I grow. I was told by the vendor that it wont hurt the orchids!

 

[paphioboy]

White mold is ok cos it doesn't get on the leaves.. I have white mold on my wooden logs all the time.. But this one is covering the leaves, so I'd better scrub it off..

 

[SaNone]

What is this

Im trying to add a picture in my signature and this is what it says what does it mean

what does this mean
Sorry, dynamic pages in the IMG tags are not allowed

 

[NYEric]

I don't know. Maybe Heather can help you. send a PM to her.