The Last Word On Nothing

Ever since I learned that lichen lives in the city, I can’t stop seeing it.

I wrote about lichen two weeks ago in this space—about learning that some lichen thrives in the city and that there are many, many more types of lichen than I’d realized. Since my first phone call with a guy who knew things about lichens, I can’t stop seeing them.

One day in December, as I wrote, I spent more than an hour on the street with my nose to the bark of various trees in the company of lichenologist Manuela Dal Forno. At one point, a teenage girl stopped to ask us what we were doing. Dal Forno explained about lichens, and challenged her to find a tree without lichens.

I’ve been watching the trees ever since. I do sometimes fail to find any lichens, but I think there’s a good chance that I’m just not seeing them. After all, Dal Forno told me that what I thought was bark color on some of the trees was actually just dark brown lichen. The bark was underneath.

“I’m just not seeing them” is probably true of a lot of things in life. I have walked the mile and a half between home and office hundreds of times. I don’t listen to podcasts or walk while reading my phone; I’m pretty much just walking and looking. But, for the first year and a half I was doing it, the lichens that are, basically, everywhere, just didn’t register. But it’s not just that. I have this sneaking suspicion that some of the houses along the route are historic. The graffiti ebbs and flows; someone else might be able to read something interesting there. All I know about the geology is one fact, from a historical marker along the route: this is the meeting of the coastal plain and the Piedmont. The freight trains are mostly a mystery to me.

This morning I was a block and a half from my office, in front of a 7-11, when I saw some lichen in the middle of the sidewalk, on the broken pieces of a branch that had fallen from one of the roadside trees. The lichen was so vibrant, lying there on the brownish bricks. The colors seemed extra intense on the rainy, gray morning. I picked up one of the pieces by a corner and carried it into the office with me.

I don’t really know why I brought it inside. I don’t know if anyone keeps lichen in captivity. It was just so beautiful, and it was going to spend all day getting stepped on, and I wanted to spend a little more time with it.

With no hand lens, my unpracticed eye could pick out three kinds of lichen on the bark. Lichen is a cooperative living arrangement–biologists call it a symbiosis–between a fungus and an algae or cyanobacteria. The top layer is fungus, but underneath lies a layer of its photosynthetic friends, building sugars to feed themselves and their host. On the side of the busy street, these algal-fungal partners were going through their tiny lives, pulling water and oxygen and carbon dioxide from the air and making a life from them as I walked back and forth underneath.

The bark was wet when I brought it in, speckled with tiny, perfectly round drops of water reflecting the green of the lichen and the white of ceiling like minuscule planet Earths. The drops lasted a surprisingly long time–the last one was still hanging on two and a half hours after I got to work, even with my computer’s hot fan blowing.

I never noticed all that beauty, all those shades of green and brown and gray, until someone told me it would be there. Now I know it grows on almost every tree, and rocks too, on my walk to work. Who would have thought that this one stretch of city could be so endlessly fascinating? And what else am I missing?

Photo: Helen Fields

Part 1 of 2: Omg! Urban lichens!
Part 2 of 2: A meeting with a lichenologist