Tree health care professionals of Vancouver, British Columbia, share a bit about this lovely and beneficial organism.
Lichens: What Are They?
If an older tree in your yard seems to be covered with moss-like growths, does this mean it’s infested with pests or has contracted a tree disease?
In most cases, it’s likely not a problem that needs to be solved. Tree lichen, which does not attack the tree, shows that the air around it is of high quality and that moisture and sunlight are available to sustain it.
Lichens are prevalent throughout the world, even in the places that are most inhospitable to life. This article will cover exactly what lichens are and what they do for the environment.
The Symbiotic Partnership that Creates Lichens
Lichens are actually a construct built through the symbiosis of two or more organisms from completely different biological kingdoms.
Unlike a parasite and its host, organisms that have a symbiotic relationship are actually each beneficial to the other. They look like plants, but they are not.
The three organisms that can compose a lichen are listed below.
- Algae: There are multiple types of algae from the kingdom Protista that bloom in various bodies of water, both saltwater and freshwater. Lichens can be formed from brown, red, green, and gold.
- Bacteria: It is a fairly recent discovery that what was known as blue-green algae is actually cyanobacteria. It is the only bacteria(kingdom Monera) that form lichens.
- Fungus: From the kingdom of the same name, fungi are plant-like growths that reproduce via spores and do not have chlorophyll for photosynthesis. Mushrooms and toadstools are the primary examples of this.
The relationship formed provides food for the fungus which benefits from the photosynthesis of the algae (or bacteria) and provides protection and moisture for the algae which normally cannot live outside water.
Where Can Lichens Live?
As previously mentioned in the introduction, lichens can live practically anywhere. Most, however, do thrive in moist and temperate climates. They can be found from one pole to the other and can be very hardy.
They have been discovered growing:
- In the Arctic
- In the desert
- On rocks
- On soil
- On tree bark and inner branches
- On rusty metal and
- On plastic.
They produce oxygen like plants, trees, and algae do, helping maintain the beauty and habitability of our world. They also act as air quality indicators because they tend to start vanishing as pollution increases. They are not bad for trees because they do not penetrate through the bark.
What Do Lichens Look Like?
Lichens’ physical growth depends on the type of fungus they are formed from.
There are three types of lichen: crustose, foliose, and fruticose.
Crustose (crust-like) lichen forms a thin layer of bright growth that is nearly flush with the surface on which it grows.
Foliose, or leaf-like, lichen looks more raised, and the growths are leaf-shaped.
Fruticose lichen is hairlike or tube-like and is the type that most resemble moss.
About VI Tree Service
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