I’m Liking Lichen on a Brick Wall

Zone 1 in our front yard is just a sliver of planter and concrete beneath the entrance stairs, but the biodiversity is amazing. One of my surprise discoveries is this clump of yellow-green lichen growing on an old brick planter.

Lichen are amazing living organisms. The Lichens of North America web page explains that lichen are fungi that do not make their own food so they have found a way to include algae or cyanobacteria in their systems to internally grow their own nutrition.


These joint efforts of life have the ability to live in harsh conditions - on rocks & sidewalks, in deserts or tundra, on cliff faces and human ruins. They survive under snow providing food for caribou and arctic rodents. Some thrive on wet tree bark and create food and nesting materials for forest creatures.

Lichens grow slowly and some may be among the oldest living things on the planet. The lichen on this brick never really caught my eye before. I don’t know how long it has been there. And that is the tricky thing about lichen: small and typically low to the ground, it is easy to miss. But because lichens protect themselves by producing chemical herbicides and even antibiotics, they could provide important pharmacological discoveries for humans. Small life must be mighty to survive. But if they are slow growing, how fast can they adapt to climate change?


Lichen are also beautiful. Check out the Lichens Home Page for some stunning photos. I think I even found my lichen, it may be Caloplaca feracissima.


Something ancient, lichen, and something new, the Internet, working together to help us see the biodiversity in our own backyards.


Lichens of North America http://www.lichen.com/index.html