Clark's Oregon Wildflower Blog: Liking Lichens

Take a walk outdoors anywhere in the Northwest and chances are you will see a lichen within five minutes. Of course if you are desperately looking for a Starbucks, you may not see a lichen; but they are there, even in urban areas. You might call lichens, "nature's graffiti."

Lichen covered trees at Rood Bridge Park - November 2013

Lichens are really low on the plant family ladder. They are so low, most can only dream of getting a picture in National Geographic Magazine - yet it has happened! Here in the Northwest, it is hard to find a tree or wooden fence post that does not have any lichen on it! Yet, their lowliness, contributes to their extreme success as an organism.

Oakmoss Lichen (Evernia prunastri) on fallen oak branch.

Most lichens can grow where no other plants can. They don't need soil or much water because they are a unique combination organism, of fungus and algae. At least that is my simplistic explanation of their relationship. This relationship allows them to thrive just about anywhere on earth. In our area, we see most on mature live trees, exposed rocks, and dead trees. Some of the ground dwellers have the ability to secrete a substance that prohibits other, competing plants from germinating. They also grow very slowly, less than 1/2 in. per year and can live a very long time. The oldest lichens are estimated to be 4000 years old!

Unknown rock lichen in the Columbia River Gorge

There are many good online sources of knowledge on lichens so I won't go into detail here, except to mention one important lichen discovery. Lichens in some areas have become bell weathers of air pollution. Scientists have figured out ways to monitor certain lichens as they succumb to constant air pollution and thereby gauge the severity of the pollution and its possible effects on other life forms.

Lichen stripes and spots along the Gales Creek trail.

Lichen and Moss on a wooden landscape post.

Map Lichen on rocks near USGS benchmark

Believe it or not, lichens have been consumed as food, but usually only in times of famine. I found many lichen recipes on the web, but most stressed the need to cook them. For example, this reference from "Eat the Weeds" was especially telling:

Most lichen are likable, but not exactly consumer friendly. What the lichen all share is acid and as such require proper preparation if they are to be eaten because unprepared and uncooked they will painfully attack your digestive track. Unprepared lichen taste like aspirin. That should motivate you to prepare it correctly. Never eat unprepared and raw lichen unless your life truly depends upon it. It probably will not kill you but you will wish it had.

From a photographer's point of view, the true value of lichens is in their wonderful colors. The hues are quite varied and can be bright and saturated.