How do you get rid of scale flies on evergreens

Question

I have a mature garden.
Plenty of rhododendrons, camellia, holly, ivy, pieris, etc.
Noticed sooty deposits on leaves this year.
Have investigated online.
Have been cutting back.
How do I eradicate this pest without destroying my garden?

Answer 1

Here is a link for several articles about treating scale that should help:

https://www.gardeningknowhow.com/search?q=scale