#1127. Mosses are boring

Mosses are boring—or so we may think. After all, “rolling stones gather no moss.”

These days we take that adage to mean that mosses are dull and static creatures, a bothersome excrescence on dynamic entities like rolling rocks—and rock bands! But in earlier centuries the phrase had exactly the opposite meaning: stay put and flourish, get rooted and grow, don’t go knocking about. As G. K. Chesterton said, “The rolling stone rolls echoing from rock to rock; but the rolling stone is dead. The moss is silent because the moss is alive.” So mosses are not boring but fascinating, in all the many ways of life. Here I hope to interest you in mosses as a fitting subject for photography. I continue a series exploring various botanical kinds (mushrooms and lichens previously, ferns to come), as I attempt to understand more about the life I see on my frequent photographic rambles in these beautiful woods, begun initially to escape pandemic confinement but continuing as a source of spiritual renewal. I recently learned a new phrase, Shinron-yoku, which means “forest bathing.” Immersing yourself in a forest cleanses the soul.

Let me pause briefly to note my sources. As in my previous posts, I have relied on those who actually know something, including in this case the standard textbook by Peter H. Raven, Ray F. Evert and Susan Eichhorn, Biology of Plants, 7th edition (W. H. Freeman, 2005), kindly loaned to me by botanist John Knox, who also provided useful commentary; the collection of elegant essays by Robin Wall Kimmerer, Gathering Moss (Oregon State U.P., 2003), which I highly recommend; and of course the usual suspects on the internet, particularly Wikepedia. My reading of these disparate sources, the tips of vast icebergs of information, has only heightened my appreciation of mosses as a photographic subject. In general, I think learning about something doesn’t detract or distract from seeing that thing; in fact, it sharpens your seeing.

Mosses are a distinctive kind of life, quite different from algae, fungi, lichens and the many other kinds of plants. Mosses are indeed plants, but they are very ancient and simpler ones. They are non-vascular plants, meaning that they lack vascula or small vessels to transport water and nutrients (these pipes are called xylem and phloem by botanists). Some would call mosses “primitive” because they don’t have a number of features found in more “modern” plants: they lack flowers, fruits and seeds, reproducing instead by spores produced in sporophytes resembling little stalks in some species, small pods in others; and they lack roots, using threadlike rhizoids instead to anchor to a substrate but not to draw nutrients and water (they soak up these vitals through their leaves, like a sponge); their reproduction is complicated beyond my competence to describe, though not as inventive as flowering plants and their pollinators. Still, mosses are green plants, performing the miracle of photosynthesis via chlorophyll (with the necessary assistance of sunlight and water), making food from air.

They are a very ancient kind of plant life, with a lineage dating back perhaps 470 million years. Descended probably from algae, they may well be the earliest kinds of plant to emerge from the ocean and colonize the land (the evidence is inferential, as soft mosses don’t fossilize well). Today they are widespread over most land areas, from poles to equator, sea to shining sea, and have diversified into perhaps 22,000 species worldwide (according to Kimmerer; other sources give lower numbers). In Arctic tundra they can constitute 50-90% of the biomass, but in temperate climes they must share space with many other kinds of plants, fungi and lichen. Even so, “there is more living carbon in Spagnum moss than in any other single genus on the planet” (Kimmerer).

Mosses are consummate communitarians, clubbing together for mutual benefit, keeping moisture in and soothing the desiccating wind. That’s why you’ll find mosses in clumps or mats or carpets, but never alone. They often grow with and upon lichens, which are the earliest pioneers on rocks; they are sometimes competitors of lichens but also visually delightful companions. Mosses are themselves pioneers, enabling further life on bare rock. Both mosses and lichens can withstand winter around here.

Mosses can grow on rocks, soils, cliffs, logs and stumps, tree trunks, or in bogs—anywhere there is adequate moisture and a durable substrate, especially alongside streams or under forest canopies. Like lichens, they “succeed by inhabiting places that trees cannot,” like cliff faces (Kimmerer). Choice of substrate varies by species. Many mosses are specific to rocks or trees, and then to only certain kinds, some preferring conifers, e.g., some deciduous trees, and there are various further specializations among these. Growing on trees, mosses are epiphytes, not parasites—that is, they don’t dine on their hosts, they merely call the tree their home while gaining nourishment and water from the air.

Mosses are useful, indeed essential, to many other species. Entire ecosystems benefit from their water retention, as well as providing niches to start seedlings. Some insects camouflage themselves with moss, and birds often line their nests with moss. But what about human use? Well, to cite just one species, sphagnum moss has been used for sterile wound dressings (in WWI), as insulation, in gardens, and also in diapers and menstrual pads in indigenous cultures. Mosses, like lichens, are very sensitive indicators of air and water pollution—as well as a good bit cheaper than technology.

Terminology can be confusing. Botanists call mosses bryophyta (not to be confused with bryophytes), a group that includes liverworts and hornworts as well as mosses, all distinct lineages but all tagged with a term derived from a Greek word that, unhelpfully, means “moss plant.” They all look like mosses! (Naturally, botanists who study bryophyta are called bryologists.) But not everything labelled “moss” is actually a moss. Some are lichens, like the “reindeer moss” on which caribou subsist in the northern winters; but lichens are a marriage of fungus and (usually) an alga, both quite evolutionarily distant from mosses. “Irish moss” and “sea moss” are algae; “scale moss” is a liverwort; “Spanish moss” is neither a moss nor a Spanish native but a vascular plant found world-wide in warmer regions. And “club moss” isn’t a moss either, but a lycophyte, although it may resemble a clumpy moss; it’s a vascular plant akin to ferns, and during the Carboniferous era its ancestors grew as large as trees—and bequeathed fossil fuels to us today.

But what’s in a name? Something quite important for botanists and those who care about understanding the actual makeup of the world, but perhaps less important for photographers who delight only in the visual appearance of things, whatever they may be called or however they are constructed or produced. Scientific interest isn’t visual interest after all. Still, these interests are far from incompatible. In fact, I think they invigorate one another.

My images, as usual, are drawn mostly from my rambles in the forests of western Virginia, with a few from Vermont and the Adirondacks. (Please note that western Virginia is not to be confused with West Virginia; it’s an easy conflation though, since the state of West Virginia was carved out of the western part of Virginia in 1861!). Hence these images illustrate only a small sample of the full variety of forms and colors (or rather, shades of green) that mosses worldwide can take. There are undoubtedly mosses in your neighborhood which I don’t see around here. All are interesting in their own way.

Mosses may appear a solid soft green mat from our towering vantage point (less than two meters, but towering in comparison with lowly mosses). From our lofty height, colors and shapes will be the main object of attention, as well as their relation to other flora—and also their soft feel, as if inviting a blissful rest. But draw closer and you will see a different world, like a forest in miniature. The resemblance to a forest is more than superficial. Robin Wall Kimmerer has a luminous chapter on this analogy entitled “In the Forest of the Waterbear” (waterbears are tardigrades, a phylum of incredibly hardy minute creatures only about 0.5 mm or 0.02 inches long, hence visible only under the microscrope—or perhaps your excellent macro lens). We can only note a few of the resemblances she mentions in comparing the moss forest with the Amazonian rain forest, a scale difference of about 3000 times! First, there often are the short spindly “trunks” of sporophytes with their tiny balls of precious spores at the tips ready for dispersal.

Then there is the dense tangle of underbrush, or rather mats of moss gamophytes, weaving around and about one another, producing the sperm and eggs that, when conditions are ripe and moist enough, collaborate to produce the spores of the sporophytes [though some mosses reproduce asexually, by cloning themselves, and some alternate between the two methods].

And finally, just as a rainforest is home to many species other than the towering trees, to incredibly diverse fauna, flora and fungi, so a mossmat is home to an incredibly diverse world of tiny creatures, from algae to lichens to various invertebrates. “Mysterious and little-known organisms live within reach of where you sit. Splendor awaits in minute proportions” (E. O. Wilson). “One gram of moss from the forest floor, a piece about the size of a muffin, would harbour 150,000 protozoa, 132,000 tardigrades, 3,000 springtails, 800 rotifers, 500 nematodes, 400 mites, and 200 fly larvae. These numbers tell us something about the astounding quantity of life in a handful of moss” (Kimmerer). You can be astonished at the minute complex life even if you don’t have the equipment to view it directly.

Mosses also combine well with other kinds of plants, providing harmonious contrasts of colors, shapes and textures.

We think of mosses as green, and that’s what they gloriously are much of the time, but that’s only when they have sufficient moisture to power up the chlorophyll factory. They can lose up to 98% of their moisture and survive, for years! When dry and desiccated they appear lifeless, in various shades of brown and yellow, or even gold.

But they are not dead, merely dormant, and they will quickly recover their green finery at the next rain, or even a fog or drizzle. They can be appreciated in all phases of their lives, even when they’re not at their manufacturing best, but I like going out in the woods to see them just after a rain. That’s when all plants look good, but mosses especially sparkle. I know it’s anthropomorphic to say this, and certainly something a scientist would never allow, but I think mosses look happy when moistened! Of course, in my personal lexicon “happiness” is another name for “flourishing,” and both are customary translations into English of Aristotle’s eudaimonia, although he applied it just to humans in his Nicomachean Ethics. I think our own lives go better, we flourish in our distinctively human way, when we do some forest bathing along with happy mosses.