Family: Sphagnaceae
Scientific name: Sphagnum species
Common name: Sphagnum moss, bog moss, quaker moss
Native of: Found mainly in northern hemisphere peat bogs, conifer forests, and moist tundra areas; some found in southern hemisphere (largest areas in Chile and Argentina); also found in New Zealand and Tasmania
Greenhouse location: Room F
Sphagnum moss is distinguished from other moss species by its unique branch clusters. Botanists use plant and stem color, shape of the branch and stem leaves, and shape of the green cells to identify sphagnum moss to the species level. Microscopic dissection is needed to identify most of the species. Botanists disagree on the total number of species in the genus Sphagnum, but many believe there are more than 300 species.
Sphagnum species are bryophytes (an informal group name for mosses, liverworts, and hornworts). Bryophytes have no roots or vascular tissue so must absorb water and nutrients from the air through their surfaces (such as their leaves). They require a moist habitat to thrive. Sphagnum mosses form dense clumps around ponds, in swamps and bogs, on moist acidic cliffs, and on lakeshores from tropical to subpolar regions.
Sphagnum moss gets its shaggy, unkempt appearance due to its profuse branching in a spiral around the upright stems. The branches often spread away from the main stem and curve back on themselves.
Sphagnum species reproduce through spores. The spore capsules are spherical, dark brown or black, and have short stalks. They violently expel their spores as far as 4 inches. Sphagnum species also commonly reproduce asexually when portions of the plants are broken off and become separate plants.
As the sphagnum moss continues to grow, its lower part dies off, turning from green to tan to dark brown. Accumulations of the dead material are called peat. Because sphagnum moss acidifies its environment, very few of the microbes normally responsible for decomposition exist. As a result, the layer of peat continues to grow at a rate of approximately 1 millimeter per year instead of decomposing. Peat bogs have formed in cooler regions where peat deposits have built up over thousands of years.
Visitors to Pinhook Bog in Indiana Dunes National Park can experience a quaking bog (the surface trembles underfoot). The sphagnum mat that eventually covered the bog during its formation encouraged a variety of species to flourish. Many of the native species growing in Pinhook Bog (including carnivorous plants) are more commonly found hundreds of miles to the north where bogs are more abundant.
Worldwide, sphagnum moss and peat have been and are incredibly important to humans. They are popular soil amendments, but the most significant use around the world is for fuel. Because peat is a major global carbon sink—trapping huge amounts of carbon dioxide within its chemical structure underground—burning it releases carbon dioxide into the atmosphere contributing to climate change. Progress is being made in harvesting peat in a sustainable way. Bog restoration and other sustainability practices are becoming more common. Unfortunately, the rate of peat extraction far exceeds the rate at which it is regenerating and more work needs to be done.
