A lichen for all seasons

Let’s go look for thousands of migrating snow geese at Red Rock Reservoir! Sorry — that only happens mid-March. 

Let’s hunt for morel mushrooms! Sorry — you can only do that in early May. 

Let’s admire brilliant orange sugar maple leaves! Sorry — that’s an activity for late October. 

Let’s go look for lichens! Now THAT you can do anytime and nearly anywhere, except underwater*! 

Lichens are not plants. They are fungi that “farm” photosynthetic algae or cyanobacteria. The photosynthetic organism gets a place to grow, and the fungus gets food produced by solar power. It may seem strange that something that appears to be one organism is actually two, but that is just a very simple example of what appears to be true for most living creatures. The human body, for example, is composed of about one-half human cells and one-half cells of many other organisms. These other cells are primarily bacteria and fungi, and they play many important roles in maintaining our bodies. 

Being composed of two organisms does make lichen reproduction “interesting.” In many lichen species, the fungus part produces spores that are carried by the wind. If these spores land in suitable conditions they will start to grow into a fungus — not a lichen. Unless they quickly find the correct species of photosynthetic partner, they will die. Lichen reproduction is chancy, but it works well enough. 

Over 450 species of lichen can be found in Iowa. Lichens can grow on soil, rocks, concrete, rusting metal, old tires and even plastic, but the easiest place to find them in Iowa is on tree bark. Finding them is easy: all you need is a 10x magnifying glass and the willingness to look carefully. Identifying what species of lichen is more challenging, but while there are some resources that can be of help, you don’t need their names to appreciate their subtle beauty. Get out and look — maybe you’ll find golden-eye lichen (pro tip: look on honey locust branches)! 

*Actually, a lichen called Dermatocarpon luridum can be found growing on rocks underwater in clear cold-water streams in northeast Iowa. 

 

Find photos helpful for identification at the Lichens of North America website sharnoffphotos.com/lichen_info/ 

Or, browse the iNaturalist app to see what others have found in the area you’re searching.