Q.Azalea problem
Several of my azalea bushes have a white feathery moss on them. Looks like moss. What could this be?

Certified GKH Gardening Expert
It is most likely lichen. It is not harmful to the plant, but if you want to get rid of it, this article will help: https://www.gardeningknowhow.com/ornamental/fungus-lichen/treatment-tree-lichen.htm
If lichen is not the issue and it's indeed moss, this article will help: https://www.gardeningknowhow.com/ornamental/foliage/moss/moss-on-plants.htm