There is a tree I pass by several times a week whenever I’m taking a walk in the woods. It’s a young quaking aspen tree growing on a southern exposure. I’ve always admired its smooth gray bark, mottled with darker patches of rough bark.

The other day, I was out walking and decided to take a few photos of this tree and its bark. Running diagonally across the light-colored surface were some diagonal lines. Animal scratches, I thought, maybe from the red squirrel that was here last week eating winterberry fruits.

As I focused the camera, I noticed the scratches were cutting not through the bark but a thin layer of lichen growth and just barely affecting the tree bark below. The smooth gray bark I had been admiring all these years was really a lichen. Even the dark rough patches, known as lenticels, were covered in minute lichens. I wondered how I had missed these lichens for so many years.

The next day I went back to the aspen with a 100mm lens and a tripod to get detailed close-ups of the lichens. I found at least three lichen species on the bark, the most interesting to me being the lichen (shown on the left below) I mistook for bark all these years. All are unidentified at this point but maybe by next year I will have figured out at least one of them.