It’s been a summer of multiple record high temperatures combined with severe drought accompanied by record high mold counts. This led me to be concerned with the greening of our maple’s bark. I learned that this “green” is a positive indicator of a healthy ecosystem; which I credit to my yard’s connecting to the county Forest Preserve. In spite of our patch of forest considered a “dead forest”, according to one Forest Ranger I spoke with years ago, because there are no longer any snakes, the presence of lichen indicates health in this maple tree habitat.
“What comes to mind when you hear the word lichen? Perhaps a plant or some sort of algae? A fungus, or a moss? Actually, lichens are combinations of green algae and fungal tissue. Each lichen specie is one alga species plus one fungus. The alga, a microscopic green plant, makes the food for the duo, while the fungus, a non-green plant, gives the pair support and soaks up moisture.” – http://www.saveatree.com
Check out this website for great insights into the varieties, benefits and uses of lichen: http://davesgarden.com/guides/articles/view/2407/.