Bill Starr: Algae and Fungi sittin’ in a tree ….
Published 1:00 pm Tuesday, February 16, 2016
It will be hard for some of you to imagine, but throughout the entirety of my youth I never made one cell phone call, not one text, not one snap chat, and no Facebook. It wasn’t because my parents were so strict; those things simply did not exist at that time. Back in the day, as my kids say, if you wanted to communicate with someone you talked face to face, talked on a land line or you wrote them a note.
Ah, the joy of sending and receiving hand written love notes. We didn’t have to worry back in those days about getting our cell phone taken up, but you did have to worry about being caught passing notes. If you were caught passing notes you might be faced with one of the most embarrassing moments of your life by having to read the note out loud in class.
In honor of St. Valentine’s Day, I am going to share with you one of the best examples of true love being revealed by a note being read in a classroom, as I remember it. How this story hasn’t made it to the Hallmark Channel is beyond me. I can remember it was a beautiful spring day sitting in biology class and there was a really pretty girl in the class; we will call her Algae. Algae got caught passing a note to the class clown. He was a really fun guy, so we will call him Fungi. Algae unfortunately had to read the words she had passed to Fungi out loud in the classroom. The note simply said, “I really lichen you; do you lichen me?” Fortunately for Algae and Fungi this relationship that was started this day could not have worked out any better. From that moment on Algae and Fungi could not live without each other, literally.
You see Algae and fungi actually formed what is called a lichen. So many of you have been bringing in plants with this lichen on them that I thought I would share this story with you. Just remember: if you see this on Hallmark Channel, you heard it here first.
I said all that to say this: lichens are that gray, green fuzzy stuff you see growing on some of your plants and trees. Lichens are composite, symbiotic organisms made up from members of as many as three biological kingdoms. The lichen fungi cultivate partners that manufacture food by photosynthesis. Sometimes the partners are algae, other times cyanobacterium, formerly called blue-green algae. Some enterprising fungi exploit both at once. The algae or cyanobacterium converts sunlight and carbon dioxide to food for the lichen fungus and in return the lichen fungus protects the alga/cyanobacterium from drying out. (They truly can’t live without each other.) The fungus obtains water and minerals from the air and the material it is growing on; it is not parasitic to the plant. The algae provides carbohydrates and vitamins. Some blue-green algae fix nitrogen that is used by both the algae and the fungus.
As plants are stressed and begin to decline, the reduced canopy allows sunlight to enter and support photosynthesis for the lichen. The presence of lichens is often an indicator of poor plant health, but it is never the cause. Lichens are harmless to plants and, if overall plant health is improved, the vibrant canopy should inhibit any sunlight available for lichen photosynthesis.
A lot of times simply fertilizing the plants will help to reduce the lichens on your plants. The combined life form has properties that are very different from the properties of the individual organisms. Lichens come in many colors, sizes, and forms. I sometimes hear them referred to as mosses; they may sometimes look like mosses, but they are not related to mosses or any plant.
If you think you might have lichens growing on your plants or trees and you are just not sure, bring it by and I will be happy to try and identify it for you. And remember St. Valentine’s Day and be sure to tell your significant other that you really “lichen” them. I bet even if you call them Algae or Fungus they won’t mind because together they become one complete organism that truly benefit from each other’s company.
Bill Starr is Sumter County Extension coordinator/ANR agent, University of Georgia Cooperative Extension Service. Contact him at 229-924-4476.