Looking for Lichens

When I found them, I was looking for lichens.

Lichens are those pale green (and sometimes yellow, orange, or bluish) things that grow on trees and rocks. They aren’t a single thing. There are many types of lichens, and they are examples of partnerships between fungi, algae, cyanobacteria, and a host of other little critters. We’re highlighting them in our Better Together exhibit this year. Not everyone knows what lichens look like, though, so I wanted to gather examples for a little display.

My search took me through a sun-specked hemlock forest. Blackburnian warblers, ovenbirds, and vireos twittered from the treetops. A broad-winged hawk gave its high-pitched “kee-ee” alarm whistle from a secluded treetop, probably defending a nest.

Across the ravine, a surprisingly loud, clear, insistent stream of tinkling notes gave away the position of a winter wren. These tiny, mouse-like birds dance around the forest floor, fallen logs, and tangled root masses. From a distance, they look like a wind-tossed leaf. They’re so hard to find and focus on that I’ve hardly ever even examined them through binoculars. Ever hopeful—my camera ready—I followed the fluttering up to a perch on a weathered stick, then down to a mossy log, and then back to a different stick. Click, click, click…I finally captured the blur of a winter wren.

The wren didn’t stop singing, but I headed up and over the hill anyway. Sticks lay strewn across the path from a series of spring storms. One in particular looked a little odd. Rubbery brown disks, about the size of quarters, clustered all along the branch, sticking out at odd angles. I poked at one with my finger, admiring the smooth, cool surface, and the springy way it flexed. Quite appropriately, these jelly fungi are called “tree-ear.”

Unlike some fungi, tree-ears do not attack live trees. They are saprobes that feed only on dead wood. The fungi do contribute to destruction, though, because they can absorb 63 times their dry weight in water. During our recent wet weather, these fungi became waterlogged and pulled down the already weakened dead twig.

Despite all these distractions, I actually did manage to find some lichens. I peeled a leafy green lichen disk off a fallen aspen tree, picked up some twigs covered in colorful crust lichens, and sliced off a few flakes of bark with powdery lichen coatings, too. With my basket just about full, there was still one more lichen I wanted to find: a pelt lichen that grows on the ground. Their leathery, brown thalli (leaf-like parts) often form patches among the moss, so I began searching the ground as I walked along the cut bank of the trail. 

After just a few feet, I spotted a patch of their dark, undulating thalli. As I reached down to pry them up, another shape materialized in my line of vision. When I found it, I was looking for lichens.

The pale brown cylinder was dissected by ridges and pits, almost forming a honeycomb pattern. It was held erect on a smooth little stem, and the whole thing was only a few inches tall. I couldn’t believe my eyes. For the six years that I’ve lived up here, I’ve always raised my eyebrows in disbelief and nodded my head dubiously when folks told me they found morel mushrooms nearby. I’m out in the woods quite a bit, and I’d never seen one up here. They’re more common even a little farther south where there is a wider array of deciduous trees and a little bit richer soil. And, of course, no one would reveal their special spot so that I could see for myself.

But there they were. Four little morels all told—unmistakably the real ones and not the darker brown false morels that turn to jet fuel in your stomach.

In her fantastic book, “Mycophilia,” Eugenia Bone writes that “Morels are probably the most fetishized of all wild mushrooms.” If people know how to identify and eat just one mushroom, it is the morel.

There is more to appreciate about morels beyond their delicate texture, rich flavor, and ability to hold butter. Most morels (there are several species) are thought to be mycorrhizal. This means that they colonize the root system of a tree. The fungal mycelia increase the water and nutrient absorption capabilities of the roots, and the tree shares some of its sugars with the morel. It’s a classic partnership, and one that’s repeated throughout the forest with various combinations of plants and fungi. In fact, scientists estimate that 90% of plant species on Earth form a similar mycorrhizal relationship with fungi.

Maybe it’s appropriate then, during my search for lichens, to happen upon this additional example of a photosynthetic organism (the tree) partnering with a fungus (the morel).

Arriving home, I gently sliced open the morels lengthwise. This is an important step in the cooking process because confirming their perfectly hollow stem is the best way to avoid misidentification. As the tidbits cooked gently in the skillet, I uploaded photos onto my computer. What wonderful things I found while out looking for lichens!

Special Request: If you enjoy Emily's book, Natural Connections: Exploring Northwoods Nature through Science and Your Senses, and think it should be available for more people to read, then take a moment and request it at your local library and bookstore! Order your copy at http://cablemuseum.org/natural-connections-book/.  Listen to the podcast at www.cablemusum.org!

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: "Better Together--Celebrating a Natural Community" is now open!