Moss grows in lawns, on stone walls, on fallen trees, on garage roofs, and in the cracks of city sidewalks — ancient, ubiquitous, and ignored.
Rolling stones gather it not. Lawn care specialists advise you to spend money to get rid of it. Because it’s tiny and everywhere, it’s easy to not see it.
But moss is really too remarkable to overlook.
Scientists now believe it was these simple plants, spreading like a carpet over the face of the then-barren earth that changed our atmosphere into the oxygen-rich state it’s now in and those allowed life to flourish here. Moss helped create our world.
“It’s all over the place,” said Cathy Hagadorn, executive director of Deer Pond Farm, the nature sanctuary in Sherman owned by Connecticut Audubon Society. “It’s beautiful.”
Birds use moss to line their nests. Four-toed salamanders lay their eggs in the sphagnum moss at the edge of swamps. Gardeners depend on peat moss to give new saplings a nice moisture-absorbing bed to start growing in.
Because they’re great at absorbing water, mosses prevent erosion. They play a part in the forest cycle, helping in the decomposition of downed trees and stumps.
And they’re great at returning oxygen to the atmosphere.
“Pound for pound, moss delivers more oxygen to the atmosphere that any other plant,” said Jim Fucetola, chief of operations at Moss Acres, a Pennsylvania-based company that sells moss to gardeners. “Fifteen percent of trees deliver oxygen to the atmosphere. For mosses, it’s 100 percent.”
Christine Cook of Easton designs moss gardens — her company is Mossaics.
Cook, an artist who moved into garden design, said she once looked out her window on a winter day. There were patches of green moss, thriving in her bare, dead-grass lawn.
“It was like an epiphany,” Cook said. “I thought ‘That’s so beautiful.’”
In Bethel, Hollandia Nursery sells some less common mosses to gardeners with a fancy for them. Its owner, Eugene Reelick, said the nursery also sells mosses people can use as a ground-cover — walk-on plants.
And because there are 15,000 to 20,000 species of mosses in the world, with each plant throwing off thousands of spores, moss is in the air.
“We’re probably breathing them,” Cook said.
Mosses are in the phylum Bryophyta. They first came out of the sea and onto land some 470 million years ago, spreading like a carpet over the then-barren earth. Over life forms followed.
Mosses are rootless. Instead, they have cell filaments called rhizoids that allow them to attach to surfaces. They’re non-vascular — they don’t have the roots, veins and water-transporting systems of other plants. Instead, their stems and leaves absorb water directly from the atmosphere.
That’s why most mosses thrive in damp places. It’s also why, in dry spells, mosses can go dormant for long periods. When it rains, they suck in the water and come back to life.
“They disappear, then reappear,” said Reelick of Hollandia Nursery.
That water can also be essential for some moss to procreate. Male plants release their sperm cells into raindrops, which splash on the female plants. Insects can do the transporting as well.
Once fertilized, the female plants release spores — one-celled reproductive units. The wind carries the spores. When they land on a suitable place, moss spores grow into new plants.
However, they can also reproduce asexually — a piece of moss can break off and start growing. It’s a little clone.
Cook said the last time anyone tried to count moss species in Connecticut — at the turn of the 19th and 20th centuries — they found about 300 species. In a state with more pollution, more development and more disturbed habitat, that number may be diminishing.
Which is also the more reason to appreciate what’s out there.
“Moss is very soft,” Cook said. “It’s very nice to walk barefoot in.”
Hagadorn of Deer Pond Farm said people can investigate the moss growing in their yard with a field guide and a magnifying glass. They can also take pictures — maybe with a coin next to the moss showing its relative size — and send it to iNaturalist, the citizen scientist project sponsored by the California Academy of Sciences and the National Geographic Society.
“People say ‘A rolling stone gathers no moss,’” Hagadorn said. “We take that to mean we’re busy and productive. But it could mean we’re always moving, never at rest. Maybe we should slow down and let a little moss grow.”