Star Sheped Hard Brittle Beasties
 

Noticed these on the underside of an orchid leaf today. Any suggestions to ID and treat?

Brown scale. Nuke it with some nicotine sulphate.
Pay attention to the labels. Nasty but effective stuff.

I agree it is brown scale which is hard to eradicate.
But nicotine is very toxic to humans and lethal if improperly handled.
You can remove what you see by hand with isopropyl alcohol and spray with some Orthonex (and I use a mask and suit for that).

Good luck!

Thanks much for the replies. I have only noticed on one plant so far. So I will try a combination of just scraping it off and Isopropyl Alcohol first.

Worst case, I expect I can buy the nicotine sulphate over the counter here...along with many other substances that have been banned in the US for 20 years.

I always used nicotine sulphate as a dip/ I'd dunk the plant in a mix(w/water) for thirty seconds or so.
Invisible scale is more prevalent than visible.
Grab a pair of channel locks, dunk, and go.
It aint anthrax. just don't get tanked and fall in the bucket.:D
Hey. It's safer than your fluoridated, chlorinated, hormonal, antibioticated water.;)
IMNSHO.:biggrin:

If you try rubbing alcohol first, I would wipe down the leaves on a weekly basis to get any of the newly hatched babies. Hopefully within a few weeks you can get things under control. Bud (a member here) has a recipe involving cinnamon extract which supposedly works really well on the majority of insects, but I can't remember the other ingredients off the top of my head.

You can also use a normal insecticide on scale, providing that you add a few drops of dishsoap to your spray bottle. The soap will help the liquid stick to the waxy covering of scale.

I wouldn't use the nicotine sulfate or any of the other stuff you say you can get, if they've been banned in a lot of places it's for a very good reason. Don't mess with your health just for some plants.

For a hard-shell scale like that, alcohol does very little, as the shell is a great protective mechanism.

Instead, try a dilute soap solution. Spray it on the entire plant, wait 5 minutes, then wipe off with a paper towel.

The soap does two things: 1) it breaks down the protective coating on the insects' shells, and on the bodies of those still in the younger stages of development, and 2) it loosens their grip on the plant, making them easier to remove.

Thanks much will try the soap trick. I have already removed most of them by hand...just on a few leaves of one plant.

Thanks.