Garden Pests and Diseases: What are the white spots., 1 by RESORT2ME

RESORT2ME wrote:
Last summer there were aphids and white fly. There's much powder from honeydew.
As weather permits, I'm resizing the landscape plants. I'd like to shred the waste and feed the compost pile.

I'm finding lots of these white things on much of all plants even though we've had freezing nights.
1. How to rid the plants of these white "bugs"?
2. Is it smart to mulch the cut-off portions and add to a compost pile... or would doing so just be spreading the problem?
3. If I make a separate pile of the mulch, will letting the pile die and sit for a year kill off these bad bugs?

I dislike throwing stuff away.