About UsNewsMeetingsField TripsYNCPublicationsLinksContact UsHome

Knowing Nature . . .

Moss in Our Midst

January 26, 2007
Jocie Ingram

Swamp Moss (Philonotis fontana) photo © Dave Ingram

A soft, green blanket of moss spreads across the forest floor. It covers rotten logs and tree trunks, and drapes decoratively from branches. Moss is plentiful in the forest, but this versatile plant can be found almost anywhere. Dry rocky bluffs may be covered with thick pelts. Wetlands and bogs are filled with spongy sphagnum, or peat moss. Moss even invades our lawns, roofs and gutters.

There is no getting away from it; we live in the midst of moss. These miniature plants come in a wide range of sizes, colours and textures. They may be dark green, emerald green, yellow green, or maroon red. Some grow in a compact, velvety cushion, and others in a loose tangle. There is infinite variety, and moss watching is a delightful way to while away the winter months.

Mosses are ancient plants that have been around for millennia. They differ from other plants in that they do not have a "vascular" system (tissues for conducting food and water). Nor do they have roots through which water and nutrients can be drawn. Reproduction also differs, in that mosses do not have flowers, pollen, or seeds like other plants.

Streamside Moss (Scouleria aquatica) photo © Dave Ingram

Moss needs moisture to survive and reproduce, which is why it grows so luxuriantly along our coast. When conditions are dry, mosses simply dry up and become dormant. Some mosses can be dormant for a very long time. With a drop of water, a dead looking dried up moss can instantly transform in to a plump, green living plant.

Mosses, hornworts and liverworts are classified as Bryophytes. Naturalists should note that some plants are falsely known as moss, such as club moss, a vascular plant, and Spanish moss, a tropical flowering plant related to pineapple. Worldwide there are about 9000 species of moss, and BC, a rich place for moss, is home to over 700 species.

The life of a moss starts with a single spore. If there is enough moisture, the spore will germinate and produce a network of small green filaments. It eventually grows into a leafy plant called a gametophyte. The gametophyte produces female or male reproductive parts. The female produces eggs in a miniscule flask at the base of the leaves. The male plant produces sperm. When immersed in water, the sperm, with two whip-like tails called flagella, swims in a corkscrew fashion to its female neighbour. If successful, the female plant is fertilized.

Oregon Beaked Moss (Kindbergia oregana) photo © Dave Ingram

The egg then starts to develop into a capsule-shaped spore-producing structure. As it grows, the capsule is suspended above the plant on a thin, wiry stalk. The stalk and the capsule are called the sporophyte, and it is dependant on the leafy green gametophyte from which it grows. When mature, the capsule starts to dry and the pressure forces off the lid. Tiny teeth line the opening, which, in response to moisture, move in and out, flicking out spores. Sporophytes are easy to find. Look for wiry, colourless stalks rising from the moss with a capsule at the top.

Most mosses are also capable of asexual reproduction. Some can grow from leaf fragments, and some produce clusters of gemmae on the leaves, which can fall off and sprout new plants.

Moss is a very important part of forest ecology. It acts like a sponge, soaking up moisture, and slowly releasing it to the earth beneath. Without moss, there would be increased soil erosion and water run-off. Moss is vital as nesting material for animals and birds. The Marbled Murrelet, a sea bird, nests high up in trees in thick balls of moss. Tiny hummingbird nests are often intricately spun with moss.

Sphagnum moss, or peat moss, is a special kind of moss that is highly absorbent and can tolerate the acidic, often hostile conditions of bogs. Bogs and wetlands, formerly thought of as waste lands, are extremely valuable carbon sinks and centers of detoxification.

Peat moss is also the most important moss to be used by humans. First nations peoples used it for insulation, as well as diapers. During the First World War, sphagnum was used as a dressing for wounds, due to its antiseptic qualities, and cotton-like absorbency. Historically, peat was cut into blocks and used as a heating fuel.

Peat mines are still in operation today, and peat is widely used in gardens. Peat is, however, a non-renewable resource, being the result of hundreds, if not thousands of years of sphagnum growth. Peat mining also destroys environmentally important bogs and wetlands.

Today, many gardeners are boycotting the use of peat moss, and the general use of moss in hanging baskets. There are many alternatives such as coir, a coconut fibre product that has qualities similar to peat. Some gardeners find that compost, mulch, and potting soil are sufficient without peat. Unwanted moss on our lawns and properties can be removed in natural ways, without using harmful herbicides. For more information, check the internet, or contact a local gardening group.

Moss is a wonderful part of our native landscape, and it is an important plant ecologically. We ought celebrate the rich abundance of this plant in our area, and seek alternatives for our gardens.