I spend a lot of time in forests that have not been logged for many years, and as a result, are recovering from being cut. Of course, logging used to be selective, the logging machine had not yet become the norm so only some trees were taken and many stumps were left. These forests, and in particular old pine stumps support a fantastic amount of plant life. Hidden behind old trees off one of my favorite trails there is a tree stump that is covered in pincushion moss (Leucobryum glaucum). I have not seen anything quite like this collection of moss that is piggybacking on itself and obviously thriving on its rich moist decaying substrate. I visit this tree stump every time I am in the area!

Most folks are not aware that moss may have been the first living green being to leave the sea. At some point around five hundred million years to three hundred and fifty million years ago an enterprising moss first attached its rhizoids (mosses don’t have roots) to bare rock and began the slow process of breaking down the surface to create soil for the plants and trees that would eventually populate the earth. What amazes me is that the structure of mosses remains almost the same as it was in the beginning…Mosses reproduce sexually and in the fall (usually) you can see sporophyte capsules waving from the tops of mosses waiting for a breeze to free the seeds that will colonize just about anywhere including in between the cracks of city sidewalks! These amazing beings can also reproduce by cloning or branching – when a small piece is broken away from a cluster. Mosses love lots of water so the best time to see them in all their glory is just after a rain when different species radiate emerald to lime to deep umber – we don’t have the words to describe the shades. All are photosynthesizing and will continue that process until a drought strikes. Then it’s as if they go to sleep. Crisp and desiccated, they may look dead but are simply waiting for the next round of moisture to swell each cell.

There are somewhere around fifteen to twenty thousand species of mosses in the world today. Mosses not only retain water but act as filters. They are an important food source for beneficial organisms; they help with soil erosion and can clean the earth of toxins. Mosses are also one of the best air purifiers around, removing a massive amount of CO2 from the
atmosphere. Combined, bryophytes (mosses and liverworts) unite with lichens and algae to take up about 14 billion tons of carbon dioxide annually. This is a truly staggering figure when rising amounts of carbon dioxide comprise such a threat to all life on this planet.

One caveat: most mosses will not tolerate heavy foot or machine traffic, so if you want to see a variety of different kinds visit the nearest wood or stream. And yet with that much said, mosses grow where other plants cannot; they can survive on cliffs, rocks, steep hills, and tree trunks. Mosses colonize the barren rocks and exposed areas of hills and make them suitable for growing larger vascular plants by depositing humus soil and plant debris. Even in winter under the snow, protected, they continue to photosynthesize.

Mosses also contribute to the environment by absorbing water from rainfall and runoff, then slowly releasing it to the ground or atmosphere. This reduces stream erosion and fluctuating water levels. Mosses inhabit every continent in the world. Providing a habitat on which many species ultimately depend, mosses underpin entire ecosystems providing shelter for other organisms such as small insects. The insects, in turn, provide food for frogs, which in turn provide food for snakes, which in turn provide food for carnivores like bobcats. Around here I have many kinds of mosses except on my paths. I prefer their soft spongy texture to grass, the plethora of greens. Ticks don’t like mosses, and the diminutive plants never need mowing!

Pincushion moss is one of my favorites perhaps because I first noticed a small perfectly round dime-sized clump on the way to the brook almost 40 years ago. This round being is now the size of a basketball! I almost always pat it when I walk by. This is a common moss that occurs throughout Europe and eastern North America stretching as far west as Minnesota. It likes filtered sun but will grow in deep shade. Pincushion moss grows in a variety of habitats including boreal, mixed wood, deciduous forests, and wooded swamps It grows in acidic soils, on rotting logs, and around the base of trees. Pincushion moss even grows on rock ledges. Like all mosses, it has leaves and stems that are tightly packed together. If you carry a hand lens as I often do, use it to peer into this miniature forest. You won’t believe what you will find there!
The inner cells are small and green because they contain chlorophyll. The outer cells are large, thin-walled, translucent, and whitish. They are filled with water when moist, and with air when dry. Male and female reproductive organs will appear on the same sea foam greenish-gray domed cushion.

The tree stump pictured is a perfect example of what happens in a forest that is allowed to re-wild itself. Not only is the rotting trunk covered with fantastic clumps of pincushion moss, but it supports wintergreen, blue bead lilies, young trees, mushrooms, and about ten other species of plants. But it is the piggyback aspect of the pincushion moss that keeps me riveted to this particular trunk because I have not seen it elsewhere.

I confess there is another reason I am so drawn to pincushion moss. It has a common name that actually describes what this moss looks like making identification simple. Leucobryum glaucum tells me nothing about what I am actually seeing. (Linneas’s classification system works for those who know Latin but because of my dyslexia I cannot use it). In the woods, I have a tendency to make up names for the mosses I meet, and then I have a picture in my mind to help me identify the moss by its correct Latin name if I am not familiar with the species. Curiously, Indigenous peoples always identified plants by characteristics that defined them, often using a verb to describe a plant’s process. For example, Robin Wall Kimmerer explains that in her Indigenous language the word for mushroom is ‘the force that brings the mushroom to life’. There is a second reason I use made-up names that’s a little more difficult to articulate. Because I feel as if I am a part of all nature I am keenly aware that I am in relationship with every plant I meet, so it’s important to me to be on a first-name basis!

If mosses intrigue you on any level, the next time it rains, don’t wait. Give yourself a treat and visit the nearest forest. The mosses that hug the ground will astonish you! And if you are anything like me, you will see them as a window into deep time.