What if there existed something in nature that could gauge air quality? There is. Though they have a preference for rough bark, lichens grow on most of the trees here. Consequently, most of the tree trunks in the woods around my home are a light grey. This is a good thing, as lichens are bioindicators of high quality air in the environment. The more three-dimensional the lichens are, the better the air quality.
Lichens are not plants. They are a mutually beneficial relationship between a fungus and algae. For more information about this relationship, see my previous post about Lichens.
When it rains, lichens act as a sponge by absorbing as much water as possible. After the rain stops, they slowly release the water back into the environment. This process keeps humidity levels in the forest more stable than if the water was simply allowed to fall directly onto the ground.
The three-dimensional properties of lichens also make them ideal places for arthropods to survive. It’s no wonder then, that birds are especially attracted to tree trunks covered in lichens. Even chickadees that have access to seed in the winter will consume arthropods for 50% of their diet.
Considering the above benefits, wouldn’t it be helpful to promote lichen growth on trees in the city?
Hmmm, interesting about lichens. Do you have a degree in biology or botany or are you self-taught, Amy? I love lichens…so beautiful. The above photo looks like it could be a beard on a little wood elf.
No science degree. I enjoy observing nature and reading about what I see outdoors in order to learn a bit more.
Those little beard-like fluffs are actually called ‘Old Man’s Beard.’
Apparently the way to promote lichen growth is to clean the air, so yes indeedy it would be nice to have city trees covered in Old Man’s Beard! Nice post, Amy.
What a great post on a unique topic. I’m sure most people pass by lichens without even seeing them. They don’t grow here in the dry prairies though!
Pat
Thanks for your comments Gerry and wildtracks.
There are some lichens on the Canadian prairies, not sure about the American. This pdf has some photos that might help you identify ones possibly in your neck of the woods (fields?) Pat:
Click to access lichens1.pdf
Gee – seems like you and Kathy and I like a lot of the same things….you just know lots more about them than I do. I love lichen and am amazed by their variety but didn’t know about all the good stuff they do. Thanx!
Well Cindy Lou, I guess we all liche lichens 🙂 Or is that ‘like likens?’
[…] further related reading, see The Benefits of Lichens on Trees and Don’t Clear Your […]