Answer: I don't know whether the patches are scale, mealy bugs, or simply lichen (a mosslike growth). Scale insects are round or oval and have a hard shell. Mealy bugs are soft and have a wispy cottony covering. Lichen is hard and thin. Insecticidal soap will take care of mealy bugs; scale insects can be suffocated with horticultural oil (keep it off the foliage), bordeaux (lime sulfur) will kill the lichen but it will take a while for it to slough off - or you can peel it off. Try to determine just what the matter might be and then treat accordingly. Best wishes with your azaleas!
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