Lichens: It Can Grow on the Trunks and Limbs of Your Trees

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One of the re-occurring calls that we have received at the Pasquotank Extension Center from home gardeners this spring is, “What is this stuff growing on the limbs and trunks of my tree?”  After closer inspection of pictures or samples we have received, it was determined that it was lichens.

Lichens are actually the combination of two organisms, a fungi and a green or blue green algae. They co-exist to mutually benefit each other. There are many types of lichens that differ in appearances. Lichens are found on many surfaces including tree trunks and limbs, rocks, etc (see picture below).

When home gardeners find it on their plants such as trees, they are usually concerned that the lichens are killing the tree. The presence of lichens can be an indication that the tree is not healthy and may need a little tender love and care, but is not actually killing the tree. More information about lichens can be found in this online fact sheet from the Alabama Cooperative Extension. Also, if you have questions about this or other gardening questions, please contact the Pasquotank Extension Center.

Lichen covering trunk of Dogwood tree

This lichen was found on the trunk of a pink dogwood. It completely covered much of the trunk of the tree.