life lessons, lichen style
Ever notice those splotches on tree bark and rocks, some brightly colored, some leafy, some with unique designs, and others that look like tiny shrubs? Then, you’ve probably observed lichens. Get out a hand lens and take a closer look. You will be delighted by a tiny world of great beauty and complexity. The patterns with which lichens decorate our world seem limitless. Prolific organisms, they produce fruiting bodies that release their spores to the elements in hopes of finding a friendly place to set up shop. I counted at least seven different lichens gathered around this live oak knothole.
So what are these tiny congregations of life–plant or fungus? The answer is both. Lichens are examples of a perfect partnership. Equal shares of give and take make their inspired existence so fertile. A fungus spreads out microscopic threads,or hyphae, like a welcome mat and invites its food producing neighbors, algae or blue-green algae, to move in. It is an irresistible deal–I’ll protect you and give you water as long as your share your food with me. The algae agrees and the two become one. No longer living just for themselves, they now exist for each other and the show is on and what a magnificent show it is!
Lichens come in several forms. Some are leafy (foliose), some are crusty and look like they have been painted on (crustose), some look like little shrubs (fruticose), and others look like a collection of tiny scales (squamulose). The black dots are fruiting structures. Notice how some have fenced themselves in with a black border.
Can you pick out the fruticose lichen? It’s center stage.
Here’s one of my favorite, albeit common, lichens. It is named for its blood red cup-like spore producing structures (apothecia). Presenting (drum roll please) : Haemmatoma persoonii.
I must show you just one more photo, although during my current state of fascination I have collected quite a few. The gray-green lichen in the center of the image has on display some rather large apothecia. They look like dinner plates!
Lichens don’t just live for themselves, they are members of the Pay it Back club. Animals use lichens for food and nesting material. Some insects wear lichens as camouflage. Lichens contribute to the creation of soil and are major contributors of nitrogen. They produce over 500 unique chemical compounds, some of which have been used for life-saving drugs. Rich natural dyes are made from lichens. Sensitive to pollution, lichens are used as indicators of the health of ecosystems. The list goes on… Lichenologists are continually discovering new lichens and wonders of their structure and function. From the Arctic to the depths of the oceans and deserts lichens populate our world. They’re part of a giant tapestry of organisms to be valued and admired, just because they exist.
If your interest in lichens has been piqued, you might enjoy perusing these websites: Lichens of North America, Seavey Field Guides and Subtropical Florida Lichens, and Lichens, Life History and Ecology.