Lichens

As flowers start to fade and leaves begin to fall my thoughts often turn to lichens, mosses and all of the other beautiful things you can still find in nature in the winter. We’ve had two or three days of drizzle; nothing drought busting but enough to perk up the lichens. Lichens like plenty of moisture, and when it doesn’t rain they will simply dry up and wait. Many change color and shape when they dry out and this can cause problems with identification, so serious lichen hunters wait until after a soaking rain to find them. This is when they show their true color and form. The pink fruiting bodies of the pink earth lichen in the above photo for example, might have been shriveled and pale before the rain.

Pink earth lichen (Dibaeis baeomyces) closely resembles bubblegum lichen (Icmadophila ericetorum.) One of the differences between the two is the length of the stalks that the plump pink apothecia sit on. They are longer on bubblegum lichen than they are on pink earth lichens. Both are very beautiful things that are rarely seen in this area. The whitish thallus, or body of the lichen, grows on soil; usually on dry acidic soil near blueberry and sweet fern plants.

Bright orange poplar sunburst (Xanthomendoza hasseana) is a beautiful lichen with its large disc shaped, sucker like fruiting bodies (apothecia) which are almost always showing. It’s found on tree bark and provides a lot of color in winter when there are no flowers to see.

Another sunburst lichen, the elegant sunburst (Xanthoria elegans) was exposed to ultraviolet radiation, cosmic radiation, and the vacuum of space for one and a half years and when it was brought back to earth it grew on as if nothing had happened. Many believe that lichens are virtually indestructible and are therefore as close to immortal as any earth based life form can be.

British soldier lichens (Cladonia cristatella) like to grow on damp wood like rotted stumps and logs, but I’ve found them on buildings, fence posts, and built up forest litter on boulders. At this time of year I don’t pass too many mossy old tree stumps without having a glance for British soldiers.

Scattered rock posy lichen (Rhizoplaca subdiscrepans) is both beautiful and unusual with its brain like body (Thallus) and orange fruiting discs (Apothecia.) This one was growing on stone in full sun. It is about as big as a quarter now, but when I first met it years ago it was about the size of a penny.

Lichen identification can sometimes be tricky. Though it resembles scattered rock posy I think this is rosy saucer lichen (Ochrolechia trochophora.) It was growing on stone, but even though the book Lichens of North America says that it grows on tree bark a little further research on the website Images of British Lichens shows that it grows on tree bark or stone. Based on that information and the fact that I can’t find a similar saucer lichen that grows in New England, I’m going with rosy saucer lichen. Even though it has rosy in its name its apothecia can range from pink to orange, according to what I’ve read.

It didn’t work out very well but I put a nickel behind these pixie cup lichens (Cladonia asahinae) to give you an idea of how small they are. The photo came out looking like golf tees in front of a full moon. A nickel is .83 inches in diameter and the round cup of the golf tee shaped pixie cup might be .12 inches on a good day. You wouldn’t fit an average pea in the cup, but a BB from an air rifle might sit in one.

I had to really push my camera to get this shot so I could show you the inside of the cup of a pixie cup lichen. The nearly microscopic red dots on the rim of the cup are this lichen’s fruiting bodies (Apothecia.) The tan colored scales are leafy growths called squamules. A squamule is a lobe of the body of the lichen (Thallus,) and some lichens are squamulose, meaning they’re made up of small, leafy lobes. I’m not sure what the objects in the cup are, but they’re extremely small.

Powdery sunburst lichen (Xanthomendoza ulophyllodes) was growing on a stone. This foliose lichen is easy to see, even when it’s small, because of its bright orange yellow color. This lichen really likes moisture and is often found growing near channels that carry water on stone or bark. This one was about the size of an average aspirin. Lichens are a good indicator of air quality, so if you aren’t seeing them you might want to check into your local air quality.

Lichens like the common goldspeck lichen (Candelariella vitellina) in the above photo are here year round for us to enjoy, and once the leaves fall many lichens become even easier to see. Look for this bright yellow crustose lichen on stone. Crustose lichens form crusts that tightly adhere to the substrate that they grow on and usually can’t be removed without damaging it.

As its name implies maple dust lichen (Lecanora thysanophora) grows on the bark of maple trees, but also on beech, oak, and basswood. One of the easiest ways to identify this lichen is to look for the white fringe around its perimeter. This is one of those lichens that I never saw until I stumbled across it one day, and now I see it everywhere. This example was about 3/4 of an inch in diameter, or about the size of a penny.

Cumberland rock shield lichen (Xanthoparmelia cumberlandia) likes to grow on boulders and that’s where I found this one. The body (Thallus) is described as being “yellow-green to sometimes bluish green” and the fruiting discs (Apothecia) are “cinnamon to dark brown.” The body of this lichen always looks like someone dripped candle wax on the stone to me.

This is a close up of the apothecia on a Cumberland rock shield lichen. Lichens are made up of a symbiotic relationship between fungi and algae or cyanobacteria. Technically apothecia are “fungal reproductive structures, in which the fungus reproduces itself through the production of spores” This is not the only way that lichens reproduce, but it is common and the apothecia are often beautiful and well worth watching for.

Beard lichens are common enough; they even fall from the trees on windy days, but this beard lichen is growing on stone and that’s very uncommon, in my experience. I think this example must be bristly beard lichen (Usnea hirta,) which can grow on wood or stone, but I must see a hundred growing on wood for each one growing on stone.

There are many different kinds of beard lichens and the differences can be subtle, but the fishbone beard lichen (Usnea filipendula) stands apart because of its resemblance to the backbone of a fish. This lichen seems to prefer growing on spruce but I’ve seen it on other trees as well. Though it isn’t rare I don’t see it often. Lichens in the Usnea genus contain usnic acid and have antiseptic / antibiotic properties. They have been used since ancient times throughout the world to heal wounds.

There are places in these woods where reindeer lichens drift like snow, and in colder climates they lie under the snow for months. As their name implies they are an important food source for reindeer, and they paw through the snow to find and eat them. Reindeer lichen is very slow growing at about an eighth to three eighths of an inch per year and if overgrazed or dug up, it can take decades for drifts like the one pictured to reappear. There are two types in this photo; the green star tipped reindeer lichen (Cladonia stellaris,) and the gray reindeer lichen (Cladonia rangiferina.)

Gray reindeer lichen in this area is silver gray, almost white, with a main stem and branches much like a tiny tree. Each branch tip is a brownish color with a globe or pear shaped fruiting body called a pycnidium. The Native American Ojibwa tribe were known to bathe newborns in water in which this lichen had been boiled, and other tribes drank tea made from it. It has also been eaten, but if you plan on eating lichens correct preparation is everything, because some can cause serious stomach problems.

It’s easy to see how star tipped reindeer lichen comes by its common name; each branch tip ends in a star shaped cluster of four or five branches surrounding a center hole. This lichen seems to be a favorite of reindeer; they will often leave the gray reindeer lichen until last and eat this one first. In Europe this lichen is used in the pharmaceutical industry as an ingredient in antibiotic ointments.

One of the most beautiful lichens that I find growing on stone is the smoky eye boulder lichen (Porpidia albocaerulescens) with its blue apothecia. The blue color seen in the above photo is caused by the way light reflects off a waxy coating on the fruiting bodies, which is very similar to the “bloom” found on plums, blueberries, and grapes. It’s as if pieces of the sky had been sprinkled on the stones when the light is right, but the apothecia can also appear black or gray depending on which direction the light happens to be coming from. The greenish-gold background color is the color of the body (thallus) of this crustose lichen.

I hope this post has shown how beautiful and interesting lichens are, and how easy they are to find. Lichens grow virtually everywhere including on building facades, sidewalks and rooftops, so they can even be found in cities. Many are quite small though, so you have to walk slowly and look closely to find them. Once you’ve seen a few you’ll start seeing them almost everywhere you go.

If you will stay close to nature, to its simplicity, to the small things hardly noticeable, those things can unexpectedly become great and immeasurable. ~Rainer Maria Rilke

Thanks for stopping in.