Believe it or not, I was walking home from the library where I had just picked up a copy of Macrolichens of the Pacific Northwest when the branch shown in the photograph fell on my head. You might say it was a sign from above. The event was not entirely miraculous, however, since the day was so windy it was difficult not to be hit on the head by falling branches. Nevertheless, the event provided me a first assignment: to identify the species present on this little wand of dead wood.
To be honest, I have made poor progress so far. I’m a babe in the ways of lichenology, and there are well over one thousand species of lichen here in my damp and rainy corner of the continent. The introductory material in Macrolichens is fascinating, though not written for the amateur; I frequently need to look up the technical and scientific terms. But another of my botany field guides, Pojar and MacKinnon’s Plants of the Pacific Northwest Coast, helpfully summarizes the joyful peculiarity of lichens. To quote at length:
“Lichens are the banners of the fungal kingdom. Think of them as fungi that have discovered agriculture. Instead of invading or scavenging for a living like other fungi – moulds, mildews, mushrooms – lichen fungi cultivate algae within themselves. Algae are photosynthesizers, and so can supply the fungus with carbohydrates, vitamins and proteins. In return the fungus appears to provide the alga with protection from the elements. A lichen is the physical manifestation of this relationship, much as a gall is the manifestation of, for example, a larval insect feeding on a leaf.”
This is a simplification, since some lichenized fungi partner with cyanobacteria rather than algae. But composed as they are of two distinct organisms, lichens nonetheless develop characteristics that are not found in their component partners when considered separately. There are questions surrounding the proper classification of lichens (they carry the scientific name of the fungal rather than the algal or bacterial half) and it’s using the term loosely to refer to distinctive types of lichens as “species” in their own right.
Scientific names aside, the common names of lichens are often (like those of butterflies and birds) great fun. A decent field guide may introduce you to lichens known as sea tar, pencil script, bark barnacle, peppered moon, lettuce lung, freckled pelt, tattered rag, forking bone, antlered perfume, sulphur stubble, devil’s matchstick, mealy pixie cup, Methuselah’s beard, coastal reindeer, witch’s hair, or hammered shield. And if these are too tame for you, there are also punctured rocktripe, blood-spattered beard, membranous dog, netted specklebelly, and seaside kidney.