It's euonymous scale. Hard to control and a lot of people suggest getting rid of the plant rather than to try.

Here is a link that might be useful: euonymous scale

Ugh it would help if I could type/spell. It's euonymus - searching for that will get you more results.

Unapsis euonymi - euonymus scale. It isn't a problem in my cool coastal climate, but on a busy holiday weekend with some gone, I guessing those are the winged males most present in your photo?

Here is a link that might be useful: euonymus scale

Yikes! You mean that all of those scale insects showed up in just one season?

I had a problem one year in a major bed of purple leaf wintercreeper. I got rid of it successfully and still salvaged the plants. But, you have to be ruthless. First I cut all the euonymus back to the nubbins. Then I carefully raked ALL OF THE DEBRIS out of the bed and burnt it. If you don't clean up immaculately, they'll be back. That made it easy for me to follow up with a very thorough spraying of hort oil. That was at least fifteen years ago. The ground cover is back with a vengence, and it's never been re-infested.

1) spelling... I made a guess at the spelling and googled it and got all kinds of hits... so I thought I guessed right... but I just had a lot of company in misspelling it.

2) "all in one season"... Yep... actually about 5 weeks. the Euonymus patch is about 6x15'... but in an area we do not go to very often... about 1/3 of it has lost its leaves... 1/3 is infested... 1/3 is still the plant I remember. When I pruned it about 5 weeks ago, it was all very healthy looking.

Will have to think about what approach to take - most likely the severe cutback and spray.

Thanks to all for your comments... any other thoughts? sent them on.

I tried for two years to get rid of this with sprays, pruning etc.. It was scale and I had to finally dig them up and get rid of them completely. Cleaned up the area really good, the local nursery even told me to get rid of the dirt (but I didnt) I did however spray it some kind of oily spray that was expensive...removed all the debris and planted easy to care for hollies...been very pleased.
Goodluck

Yep, Euonymous scale. I have one shrub and I sort of live with it. I control the scale by annually thinning the shrub for better air circulation, often removing many of the older branches. In Spring, I spray w/ horticultural oil.