Small brown oval disc's

[Bobkap]

I have a collection of Phal's in doors on humidity trays.
I just started to notice brown small oval shaped disk's or shell like growths. They are on the top of the leaves and the underside as well. They are small and I don't think my camera can capture the images. They come right off with your finger and when you run the plant under water they fall right off. Some of the spikes have them all around the spike.
Does anyone have any info is it a bugs shell or a growth?
I looked at them under a magnifying glass and the underside seems hollow like a shell.
No new plants have been added within the last 7 months they are on most of the plants.
Can anyone on the board suggest?

[Whimgrinder]

Originally Posted by Bobkap

I have a collection of Phal's in doors on humidity trays.
I just started to notice brown small oval shaped disk's or shell like growths. They are on the top of the leaves and the underside as well. They are small and I don't think my camera can capture the images. They come right off with your finger and when you run the plant under water they fall right off. Some of the spikes have them all around the spike.
Does anyone have any info is it a bugs shell or a growth?
I looked at them under a magnifying glass and the underside seems hollow like a shell.
No new plants have been added within the last 7 months they are on most of the plants.
Can anyone on the board suggest?

This sounds like Scale insects, Can you please provide a photo?

[estación seca]

Sorry this had to happen.

You're giving a wonderfully accurate description of scale insects. They can be hard to kill because the shell prevents a lot of things from getting to the insect's body. If you search the

Pests and Diseases

section of this board you will find a lot of ways people get rid of them.

To be brief, when an entire collection is infested, treatment with a commercial pesticide, at intervals, for 3-5 treatments total, is likely to be the only method that helps.

You will need to take your entire collection to the bathtub. Then you will need to spray the tops and bottoms of all leaves, and soak the medium and roots. Then you will need to let them dry, and put them back. You will need to repeat this once every 10 days or so for 3-4 times total.

Repeated treatments are needed because eggs often are not killed by spraying, so you need to keep killing the newborn bugs before they mature and can reproduce.

[Bobkap]

You know when you said Scale that's the first thing that I though of. What product would you recommend for he process of getting rid of the bugs? Thanks the Orchid Board is awesome the members are ++10!

[estación seca]

It depends on what is available. Go to a good garden shop and ask for advice. Big box stores here no longer carry anything but permethrin and semi-synthetic derivatives thereof, which often aren't too effective on scale. Realize the pesticides mostly smell bad and can hurt you, so be careful when you use them, and wear heavy gloves.

[Orchid Whisperer]

Look for Bayer products containing imidacloprid. Good choice for scale because it is systemic. Same chemical used in Advantage brand flea products for dogs, but the flea stuff is hundreds of times more concentrated. You can look on the St. Augustine Orchid Society web page, follow links relating to pesticides, you will find a table for application rates for these products.