web analytics

Like Lichens

By Ranger Steve Mueller

There are small beautiful brown moths with red stripes on their wings that run lengthwise away from the head. People occasionally notice their beauty and ask about them. They are Lichen Moths that likely feed on lichens.

These moths and lichens are creatures few notice. It is incredibly difficult to locate caterpillars on lichens. They are small and blend in well. To study the moth’s nature niche, scientists collect adults and place them in a container with lichens so the moths will oviposit their eggs. Then they can be studied as they grow.

I see a half dozen lichen moths each summer but tens of thousands of lichens grow at the sanctuary. Even if I knew one of the caterpillars was present in lichen, it would be hard to find because they camouflage well.

Lichens can be abundant but their numbers decrease rapidly in response to air pollution. Like all living creatures some are more resistant to pollution than others. They are used to monitor air quality and for fabric dyes. They have antibacterial and anti-germination chemicals studied for medicinal and agricultural uses. Perhaps your antibiotics are lichen based. That alone is reason for us to “like lichens” and protect the habitat. They are good neighbors growing on trees, rock, fences, or almost any place they can gain a foothold.

They use objects as a place to perch much like a bird uses a branch to stand on. They are not parasites penetrating the tissues of organisms for nourishment. Their nature niche method of survive is unique. A lichen is composed of two organisms that live together for survival. One is an alga and the other a fungus.

Visually think of a magnified lichen like a fishnet with tennis balls caught in open webbing spaces. The fishnet represents the fungus that cannot produce food but it holds water like a sponge. The tennis balls represent algae cells that capture sunlight energy to produce food. To survive the fungus grows hyphae that penetrate the algae cells to acquire food to live.

One might think of the fungus as parasite but instead scientists consider the algae and fungus as mutual symbiotic organisms that help each other survive. It is obvious that the fungus benefits by extracting food energy from the algae. The alga benefits because alone it would dry and die. It is like corn and people. We plant corn and it gets to survive abundantly even though we eat it. Without people, corn would be rare on Earth. Without the fungus, the species of alga that depends on the fungus would be extremely rare.

Walk around your neighborhood or visit a county, state, or national park and notice lichens. There are three major kinds or groups of lichens based on growth form. If you have noticed lichens, it is probably the leafy or shrubby growth forms that captured your attentions. Lichens do not have leaves but examine some growing on a tree. They tend to grow from the center outward forming a circular growth like a paper plate. They are thin from top to bottom and spread a few inches wide on the tree trunk. They grow on rocks in the same manner.

They need a substrate to stand on and do not use it for food. Most lichens are only an inch to a few inches across but several might grow together. The leafy ones shaped like a paper plates are called foliose. 

The second group is called fruticose because they grow like miniature shrubs. A striking one is the British Soldier or Red Caps. They have gray/green appearing stem-like branches capped with bright red tops. The red caps are the reproductive structures. These are found in a variety of habitats and frequently colonize bare sand where little else can grow. Keep in mind they are not gathering nutrients from the soil like farm crops. The fungus holds moisture the alga uses for adequate water for photosynthesis and food production to support both.

The third group is crustose and appears like a crust on the surface where it grows. They are often seen on gravestones. The three groups in the Great Lakes region have about 700 species comprising a miniature world. Like lichens, enjoy their beauty, and associated species like lichen moths.

Natural history questions or topic suggestions can be directed to Ranger Steve (Mueller) at odybrook@chartermi.net – Ody Brook Nature Sanctuary, 13010 Northland Dr. Cedar Springs, MI 49319 or call 616-696-1753.

This post was written by:

- who has written 15566 posts on Cedar Springs Post Newspaper.

Contact the author

Leave a Reply



Cedar Car Co
Kent Theatre
Advertising Rates Brochure

Get Your Copy of The Cedar Springs Post for just $40 a year!