Cut any overhanging limbs that shade the area where the lichen is growing.
Run a rake over the lichens to break them up and remove them from the soil. Add the lichens to your yard waste container.
Remove a soil sample and take it in to your local university extension for testing. Soil testing will determine the correct amount of soil amendments to add to your garden. You can also have the lichen variety confirmed to determine the appropriate type of fungicide to use.
Apply fungicide to the lichen according to the instructions on the label. Following the label instructions is often a legal requirement.
Spread 1 to 3 inches of compost over the lichen area and work it to a depth of 6 inches if a soil test cannot be performed. This will improve soil nutrition and prevent the future growth of lichen.