Call in a Cooperative Extension Agent or a Master Gardener to help identify any health problems of the plants that have lichen growth on branches or bark.
Carry out suggested measures to increase plant health that would lead to increased canopy shade, which would result in decreased lichen growth.
Put shade cloth over affected branches or trees to temporarily create shade. Cut shade cloth to fit individual azalea branches or tree trunks. Tie the shade cloth down with rope or string if necessary. Lichens will eventually die without sufficient sunlight.
Remove lichen physically. Moisten the affected area with water, or wait until after a soaking rain.
Gently rub affected areas with a soft scrubbing brush or pad. Rinse the brush or pad frequently in a bucket of water. Empty the bucket and refill it with clean water as needed.