Could be scale (a sucking insect).
Have you tried scraping them off with your fingernail?

-Robert

I googled scale on Osmanthus (sweet olives) and they can be a problem. One site recommended horticultural oil sprays.

Good luck!

-Robert

Here is a link that might be useful: scale on sweet olives

My goodness, you poor thing!

You have a few options, the first working much more effectively than the later.

You could use a systemic and you will see them fall off dead.
Or you could use oil sprays as Robert says and slowly suffocate them.

What ever you see, you could also use a cotton swap with alcohol and swipe off what you see.

There is also insecticidal soaps which will slowly kill them

The best way to rid them for good is systemically and that is what I would do for mine.

Mike

This post was edited by meyermike_1micha on Tue, Dec 4, 12 at 19:30