I've been having a problem for a long time on my thick leaf orchids
(mostly phals, but now a dendrobium and another one). When you wipe the
leaves with a wet paper towel, red "dust" comes away. The leaves can
show this red dust too, but often on the bottom (and sometimes tops of
the leaves) there is white/brown stuff that can't really wipe away.

The leaves look really sickly.

Any ideas what sort of creature or virus I might have, and more
importantly, how I can stop this short of getting rid of all of the
beautiful thick leaf orchids?

Thanks.

Do you use well water? Almost sounds like rust.

As far as what is wrong, is there any way that you can either post a picture
to alt.binaries.pictures.orchids, or a link to a photo share site? At least,
give us a better description. I'm not picturing the white and brown spots.

Diana

The red "dust" sounds like mites.

The white/brown, harder to say. Could perhaps be scale, and/or scarring
from past damage??? You could probably get a more definitive answer if you
could post a picture on abpo ...

Kenni


"OrchidPop" wrote in message
oups.com...
I've been having a problem for a long time on my thick leaf orchids
(mostly phals, but now a dendrobium and another one). When you wipe the
leaves with a wet paper towel, red "dust" comes away. The leaves can
show this red dust too, but often on the bottom (and sometimes tops of
the leaves) there is white/brown stuff that can't really wipe away.

The leaves look really sickly.

Any ideas what sort of creature or virus I might have, and more
importantly, how I can stop this short of getting rid of all of the
beautiful thick leaf orchids?

Thanks.

It sounds like mites to me too. Just went though a bout with them. It was
recommended to me to use an insecticidal soap according to directions. You
will need to treat at least three times a week apart to get them all. The
soap seemed to work for me.

If there is a greenhouse near you they might have a microscope and could
verify their presence before treatment. Call them first though.

Bob

"Kenni Judd" wrote in message
...
The red "dust" sounds like mites.

The white/brown, harder to say. Could perhaps be scale, and/or scarring
from past damage??? You could probably get a more definitive answer if
you could post a picture on abpo ...

Kenni


"OrchidPop" wrote in message
oups.com...
I've been having a problem for a long time on my thick leaf orchids
(mostly phals, but now a dendrobium and another one). When you wipe the
leaves with a wet paper towel, red "dust" comes away. The leaves can
show this red dust too, but often on the bottom (and sometimes tops of
the leaves) there is white/brown stuff that can't really wipe away.

The leaves look really sickly.

Any ideas what sort of creature or virus I might have, and more
importantly, how I can stop this short of getting rid of all of the
beautiful thick leaf orchids?

Thanks.

You don't actually need a microscope -- a jeweler's loupe or even a good
magnifying glass allows me to see mites.

If your weather is not too hot, an oil spray [Neem, Ultrafine, whatever]
might be your best bet. But if you're having the kind of heat wave we've
been having here in south Florida, oil can be dangerous. [Think about
stir-fry :( ] Rubbing alcohol [cut 50/50 with water] or soap [any kind --
"insecticidal soap" is a redundancy] are other possibilities. But all of
the above are only "contact" killers, with no residual effect on the
critters. Which means it only kills the mites it gets on -- if you miss
any, they'll just start up again.

Because you say this has been going on for "a long time," I suspect the
critters are thoroughly entrenched, down in hard-to-reach places like leaf
axils, under old "sheathing" on the den(s) and other(s), and maybe even down
in the potting media/roots. So if possible, I would recommend that you
follow up with a systemic miticide -- Floramite, Avid, Kelthane, Pentac ...
All getting harder and harder to find, esp. in hobbyist quantities. OFE in
Miami did have Avid in relatively small bottles, last I looked, and they do
ship. Or possibly your closest local orchid nursery has one of these on
hand and would sell you a small quantity [BYOB to put it in G].

Otherwise, repotting may be required ...

Good luck, Kenni

"OrchidPop" wrote in message
oups.com...
I've been having a problem for a long time on my thick leaf orchids
(mostly phals, but now a dendrobium and another one). When you wipe the
leaves with a wet paper towel, red "dust" comes away. The leaves can
show this red dust too, but often on the bottom (and sometimes tops of
the leaves) there is white/brown stuff that can't really wipe away.

The leaves look really sickly.

Any ideas what sort of creature or virus I might have, and more
importantly, how I can stop this short of getting rid of all of the
beautiful thick leaf orchids?

Thanks.