Pictured Rocks National Lakeshore is home to more than 230 species of lichens, including some rare for the Great Lakes region. Visitors can find lichens in almost every lakeshore habitat, from bare ground to open sand plains, on rocky outcrops along waterfalls, in white cedar wetlands, and attached to the bark of many mature trees.
Air Quality Sentinels
Some lichens make excellent air quality bio-indicators as they are particularly sensitive to airborne contaminants. Lichens are so sensitive to sulfur dioxide that it is possible for scientists to calculate the amount of this pollutant in the atmosphere by mapping the occurrence or disappearance of certain lichens in a given area. Researchers have found these particular species here at Pictured Rocks with no signs of damage due to pollution, indicating that air quality in this region is quite good.
Did You Know?
When the 729-foot freighter S.S. Edmund Fitzgerald went down on November 10, 1975, the last land-based communication to the ship was from the Grand Marais Coast Guard Station. This station and the Munising USCG Station are now managed by Pictured Rocks National Lakeshore. More...