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| AFTER THE STORM...YESTERDAY MORNING |
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| LICHENS ON YOUNG SUGAR MAPLE TREES |
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| LICHEN COLONY ON A YOUNG RED OAK TREE |
Taking Buddy for a run down Old San Road yesterday I was struck by the number of lichens on the oaks and maples, and how obvious they are in the bright sunshine and glistening snow. There are many, many kinds of lichens, epiphytes that grow harmlessly on the bark of tree trunks and branches, as well as on rocks. Those pictured are crustose (crusty) lichens; there are also foliose (leaf like) lichens, and others that look like miniature trees or shrubs. The beauty and diversity of these odd living organisms is striking, and they encompass their own, separate branch of botany. Although I have always found them fascinating, I have never studied them seriously. And that's a shame.
Lichens are a symbiosis between a fungus, which provides the growth substrate, and a blue-green algae, which provides the photosynthesis which nourishes the composite organism. There are also lichens which are a symbiosis of a fungus and a photosynthetic bacterium, that are very prevalent on the rocks along the shores of Lake Superior and other northern bodies of water. They are orange and yellow rather than green in color, making the rocks look as though they have been splashed with luminescent paint. Lichens are also very sensitive to air pollution, and their abundance can be seen as an indicator of good air quality, and their absence the inverse.
Lichens also live on conifer branches (I see them most often on spruce trees), occasionally so heavily encrusting them that some of the branches may die, but they are not parasitic in any way. These strange and lovely organisms should be accepted as part of the ecology of the landscape, as they are by and large not harmful, and provide yet another perspective on the economy of nature.
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