I have several coontie palms that have what looks to be scale (little round brown things) and black soot on the fronds. I've used soapy water and a tooth brush to clean it up, but it keeps coming back. I'm not sure what else I can do. Is there something that can rid this for good?
I usually have this happen on citrus trees at my place in Boca Raton. It appears to be the results of bugs on the upper leaves pooping/tinkling on the tops of the lower leaves and this fairly thick layer of black sooty mold grows in the poop/tinkle/whatever. After the tree has bloomed and the fruit is set I give it a spray of citrus insecticide and the problem goes away with the bugs.
I realize I'm not speaking at a high level of sophistication but I don't think you want a doctoral thesis, just a way to get rid of the black crud.
Good luck. Let us know what you do and whether it is successful.
I have bought the Organocide and will use it this weekend. I've uploaded a picture of one of the plants....maybe it will help. I haven't found anything on the internet like this.
It looks like some type of scale or even eggs of a moth. I have searched and searched and discovered that the Zamia is the larval food for the echo moth. I can't seem to find pictures of the eggs of this moth. Seen anything like this around? http://www.daltonstate.edu/galeps/webpages/arctiidae/Secho.htm
Since the coonties are in my screened area, I wouldn't miss seeing moths. And that I haven't seen. However the red scale looks like it could be it. I'll clean them up as best I can and then spray.