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What is it that I have heard about February? That it’s the three months between January and March? Something like that. Perhaps that’s the case for the folks on the East Coast right now as they plough feet of snow to either side of the driveway, as the snow begins to turn black with pollution, as skeleton-like deciduous trees poke up toward the bleak and cloudy sky.
Yes, I know in the countryside there are many unspoiled acres where the snow scene is picture perfect, where everything is hushed and slow and quiet except for the swish-swish of your cross-country skis and the beat of your heart as it bursts with the beauty of it all.
There are February days here when my heart, too, responds with joy at the sight of the frost-covered leaves of the manzanita and scrub oak, the ever-so-fragile layer of snowflakes as they balance on the thinnest of aspen twigs, and the coniferous forest trees are decorated with jewels of frozen water drops as though challenging us to believe that today, surely, is Christmas day.
Then, just at the point when I can hardly believe how such a sight fills me, I lift my gaze up to and beyond the tops of the pines, and the sky is so indescribably blue and clear it literally takes my breath away. It’s too early for any flowers to poke their little heads up above the remaining snow.
What would be the point—there’s nobody around to do the pollination job that is the raison d’etre for the flower, i.e., make seed, be reproduced. But just because the flowers aren’t busy blooming doesn’t mean that something else out there, almost as colorful, isn’t busy with growth, and doing it without leaves, or roots or flowers!
This time look down, not up. The world of rocks and bark and soil and leaves and old, unwashed cars and—yes!—even animals (on the carapace of a Galapagos land tortoise, or the larva of a lacewing!) is the world of this colorful, curly stuff.
Lichens. This is the time of year to be out lichen-watching, looking for their bright glorious shapes and colors. Lichens are nature’s artwork. They are survivors. They are mini-ecosystems.
And for a long time they were ignored by botanists, with even the father of taxonomy, Carl Linnaeus, referring to them as “the poor peasants of the plant kingdom.” They are wonderfully peculiar.
Lichen is, in fact, a pretty cool partnership between two organisms—a fungus and an algae—both needing each other to survive, one to provide food the other to provide structure. A symbiotic relationship. However, back in the late 19th century some scientists thought the fungus was boss and that the green algae was forced into service like a slave. They had the picture right, but the function wrong.
The intricately fine threads of the fungus, which cannot provide its own food, weave themselves around the green photosynthetic algae cells, which do provide the food.
One old scientist, as far back as 1877, likened the fungus threads twined around the algae to the meshed web of a spider, writing “. . . but, whilst the spider sucks out her prey and throws it aside when dead, the Fungus stimulates the Algae, found in its net, to more lively activity. . .”
In fact, the actual presence of all those fine fungal threads does result in the availability of more than usual sugars from the algae as, essentially, it is providing food for two! It seems like a pretty good partnership to me—one is the breadwinner, the other providing a strong home environment.
The palette of colors includes bright yellows, reds, oranges, greens, grays and blacks. Here’s a challenge for your next ramble through the woods: see how many colors you can find; try to discover the three growth forms of lichens—crusty ones tightly holding on to the base of rock or soil, foliose or leaf-like ones with a clear upper and lower surface and that are almost always attached to rocks, and the erect or hanging lichens (like a beard)—fruticose. And try to figure out the age of the beauty—most of our lichens grow very slowly, as in the thickness of a Sharpie stroke a year!
So, who likes lichen? Santa’s reindeer like to eat it, and so do our pronghorn and mule deer. Birds love it inside and outside of their nests, for comfort and for camouflage.
People in the arctic make a dish called “stomach ice cream”—the partially digested lichen from a caribou’s stomach, mixed with raw fish eggs. Yummy! Humans have benefited from lichens by using them for food, beer, clothing and dyes (the Navajo use lichen dyes in their beautiful blankets), perfumes (ground up moss lichens were dusted into wigs 300 ago to improve their odor!), internal and external medicines, decoration, scientific age dating and so much more.
Has our human relationship with lichens been, as would seem fitting, a symbiotic one? Hardly. We have buried them under asphalt, concrete and buildings. We have so polluted the atmosphere that some lichens have died out (they are bioindicators and can detect, measure and map pollution).
We have converted old-growth forest systems to single lumber crops, thus wiping out the diversity of habitats and microclimates in which lichens thrive.
We have introduced foreign plant species that, by overcrowding, can affect the light quality necessary for healthy lichen growth. And here in the arid west we have destroyed large tracts of delicate microbiotic soil crusts by poor overgrazing practices in the past, and negligent off-road vehicle use today continues the practice. Rock climbing too, has an impact on rarer species hidden in the crevices and cliffs.
It would be interesting, if it were possible, to see satellite images of our landmasses in the past and the present, comparing the patterns of lichens then and now. In the end the disappearance of lichens may be the very real indicator of our human odyssey on Earth. |
