By Steve Roark
Volunteer, Cumberland Gap National Park

Anyone who has walked in the woods has seen areas of rock or soil covered with a thick, green carpet. Moss often just blends into the forest background and goes unnoticed, but it is an old and venerable life form unique to most plants you find.

Probably the most common moss in our area is called pin cushion or carpet moss. It is one of the true mosses under a plant class called Musci. Moss is very different from other plants in that it has no true roots that take in water and nutrients from the soil. It has only structures called "rhizoids" that serve to anchor the moss in place. Water is absorbed throughout the plant surface, and it has the ability to store a good deal of it for dry times and for reproduction. Part of the life cycle of mosses is that reproductive cells swim to join other individuals of their species, kinda of like the animal world.

A clump of moss is actually a group of small individual plants, each made up of spongy stems covered with small green leaf-like structures. Moss has no true flowers but sends up a golden thread-like structure with a spore capsule on the end that releases spores to grow more moss plants.

Most moss species prefer moist, shady locations, but can also be found on dry ridges and slopes. It prefers acidic conditions and can be used as an indicator of acid soil. You can find it in pasture fields that badly need lime. Since it doesn't need soil for water or nutrients, moss can grow on solid rock, where it has little competition for growing space. Mosses are often the first plants to colonize exposed rocky areas and help break down rock by the freezing of water retained by the plant and by the action of secreted chemicals. On logs they delay water loss, speeding up the growth of decay organisms. Mosses also serve as cover for insects and can be found as a building material in some bird's nests.

There are lots of moss species, and often hard to identify. But there are several groups of mosses that are common in our area and easy to figure out. Pin Cushion Moss is very thick and soft and often has a rounded dome appearance. Rose Moss indeed looks like a green rose flower. Tree Skirt Moss likes to grow at the base of trees. Fern Mosses reminds you of small ferns. The Haircup Moss group has leaves forming a starburst pattern.

Mosses are an ancient plant group, having been around far longer than flowering plants. Fossil records indicate they existed over two and one half million years ago. So the next time you see some moss growing in the woods, maybe it deserves a closer look.