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Bark Rash Lichen

When I walk the forests, I'm drawn to a group of living organism of which I have little knowledge - lichens.

I know their forms, that they are composed of a fungus and an alga, a bit about their reproduction, and that they are often encountered in surprising locations.  I've seen them in our forests, in the Arctic tundra, on rocks in Antarctica, hanging from trees in New Zealand, in the Amazon, and in many other places.

But I almost never know what they are or aspects of their individual natural history.

Cobalt Crust, Terana caerulea. A lovely fungus

Nature Notes
by Bob Thomas

One of the most beautiful fungal species is cobalt crust, which is also known as “velvet blue spread,” or simply “blue velvet on a stick.” Although its correct scientific name is Terana caerulea, it is most often referred to as Pulcherricium caeruleum. Those pesky rules of nomenclature exist to ensure an orderly system of taxonomy based on rules of priority, but their adherence occasionally creates change, thus causing confusion for the non-specialist.


Natural History Notes
by Bob Thomas

Have you ever seen mystical flashes of blue-green light in the night? If you are one of the lucky ones who say “yes”, then you have observed bioluminescence, or biologically produced light. It exists in a variety of living forms: fungi (foxfire), fireflies, marine fish, squids, worms, and jellyfish. It is known on land and in the sea, but not in freshwater. Below the zone of sunlight penetration in the sea, it is the rule, with virtually all organisms bioluminescing.

Lichens and Katrina

Nature Notes
by Bob Thomas

Lichens are a common life form, and they are diverse and abundant in coastal Louisiana.

The grayish-green thalli (the vegetative body of the lichen) of our most familiar forms grow on most species of trees. Live oaks always have a healthy population, and some, like the one shown in the photos to the left, may be profusely covered.

Unless one is a lichenologist, it is easy to overlook lichens' presence, especially when driving past stately oaks in urban areas.

Fairy Rings

Article Title
Fairy Rings, Delta Journal, The Times-Picayune, June 17, 2007, C9

Delta Journal

by Bob Thomas

Ever notice the circles of mushrooms that frequently appear on our neutral grounds and in our yards the day after a hard rain during our humid summer months? People often refer to them as “fairy rings” because fairies supposedly dance in them at night.