Hi Sbg. I know this very well! There are several agents as I am sure you know that can cause galls on different plants. Animals such as Weevils, Flies, Moths, Sawflies, Mites, Eelworms and Bacteria. This one though is a fungus called Azalea Leaf Gall.

Just looked this up about it.

http://plantclinic.cornell.edu/FactSheets/azaleagall/azaleagall.htm

thanks fractal Never thought of it as being a gall. but certainly fungal in texture. I will have a read.

well it says to remove them before they turn white. oops too late. But I will remove them tomorrow.
very interesting
thanks fractal.

Wow, reading all these answers to questions reveals amazing facts. This site is certainly addictive as well as informative!