What is growing on my trees? LICHENS!

What are lichens? Lichens are actually two separate organisms, a fungus and an alga, working in a symbiotic relationship. While they are often found growing along with moss, the two are not related. Moss is an actual plant that favors the same growing conditions as lichens. Lichens can grow on any rough surface which allows them to anchor

Lichens pull water from the air so they favor wet/humid conditions. During periods of extended rainfall these organisms “turn on” and can become quite vibrant and prolific. During periods of dry weather lichens “turn off”, that is they go dormant and become brittle. They do no damage to the trees and shrubs they attach to. In fact, attempting to remove lichens from your trees via power washing, brushing, etc. will do far more damage

Seeing lichens thru out your landscape is a good thing as they are excellent at removing various pollutants from the air. They filter air in much the same way a marsh or retention basin will filter water.

So what about Moss? Just like lichens, moss does no damage to trees. Tree trunks simply provide ideal growing conditions by providing shade and moisture as water flows down the trunk during periods of rain. Similarly, Moss does not kill turf grass – rather, the presence of moss is an indication that an area is too shaded for turf grass to become strongly established. The Moss is not “choking out” the grass, the Moss is claiming ground vacated by grass due to inadequate sunlight.