Frequently, customers come into the Garden Center with pictures or samples of lichen they have in their Garden. Most often people think that the lichen is killing their tree or plant. This is NOT the case. Lichens are moss like organisms that grow on the bark and branches of trees or shrubs. They do not attack and kill. They are a very natural part of the landscapes and wooded areas.
Plants covered with lichens may look trashy, but there are reasons why they are covered. The lichens grow rapidly when exposed to sun and a bare plant or plant with a thin canopy create ideal locations for lichen to proliferate. If a plant is declining and covered with lichen, there is some other cause. Consider other possible causes of the plant’s poor growth like stress, drought, diseases or insects. Lichens are not considered pests. There are no chemicals we can spray to legally control lichens. You can try picking them off the bark or pruning out covered branches, which may already be dead.
So, after knowing what lichens are, don’t panic and blame them for killing your plants. Rule out lichens as the cause and start checking for other possibilities.