Sphagnum moss

Description: Sphagnum mosses are a genus of mosses that thrive in damp places. There are around 200 species of sphagnum moss, and we have about 50 species in Norway. The colour can be green, red, brown or yellowish. They grow in dense carpets. Sphagnum mosses have a particular way of growing, where they grow at the top while the lowest part is brown and dead. The dead part of the moss does not break down, because sphagnum mosses contain bactericidal substances. For this reason, dead sphagnum moss is continually built up at the bottom while the plant grows at the top. The dead parts are pressed more and more tightly together and, after many years, turn into peat. In this way sphagnum moss can help create ‘land’ where there was once open water in the bog.

The leaves of sphagnum mosses are made up of two different types of cell. One type is ordinary plant cells that can carry out photosynthesis. The other type is special cells that can store water. When it is dry, these cells fill with air and the moss will look white. When water returns, the cells fill up again and the plant regains its colour. Because they have these water-storage cells, sphagnum mosses can soak up water equivalent to 20 times their own weight (Bjerkely 2018). This water-storage ability can help prevent flooding when a lot of rain suddenly falls, because they soak up the water. Try taking a sphagnum moss and another moss. Dry both. Weigh them while they are dry. Place them in water for 5–10 min. Let them drip off a little and weigh again. Use: Because sphagnum mosses contain an antiseptic substance that is bactericidal, they have over time been used for storing fish, vegetables and so on. They have also been used by women as sanitary towels during menstruation and as nappies for children. This use exploited both the antiseptic effect and the ability to soak up water. We can also use sphagnum moss as toilet paper when out on a tur, and to wash our hands after a toilet stop. And if you get an insect bite, rubbing the spots with damp sphagnum moss can be soothing.

Peat and sphagnum mosses have over time been harvested in large quantities, both for fuel and, in our own times, because peat is a good soil improver and growing medium. Large quantities of peat-based compost are therefore sold in garden centres and nurseries. The problem is that it takes nature many years to build up layer upon layer of sphagnum moss, while it can be harvested very quickly (see the section on the importance of bogs). Habitat type: Water and bog Edible: No Written by: Lærke Stewart

• Moss

  We have over 1,000 moss species in Norway. Mosses do not have roots like trees and other plants. They have anchoring organs that hold them fast to the ground, but they do not draw nutrients and water up through these. They get nutrients and water from the air and take it in through the leaves. Mosses can withstand drying out for a long time, but they need water and moist air from time to time in order to complete their life cycle.

  Mosses vary both in colour and in their way of growing. They can grow on soil, in trees and on rock. Mosses are found in almost all habitat types, but especially in bogs and the mountains they can be very dominant and in fact contribute more to photosynthesis than other plants. In the forest there is also often a great deal of moss growing. In a small area there can be many different species of moss.

  In the past, mosses were used to seal roofs, walls and boats. Today mosses are used in environmental monitoring. Mosses are, for example, used in studies of air pollution, because different species react differently to different substances. A number of moss species have medicinal properties, for example an antibiotic effect.

  • Sphagnum mosses

    Sphagnum mosses are a genus of mosses that thrive in damp places. There are around 200 species of sphagnum moss, and we have about 50 species in Norway. The colour can be green, red, brown or yellowish. They grow in dense carpets.

    Sphagnum mosses have a particular way of growing, where they grow at the top while the lowest part is brown and dead. The dead part of the moss does not break down, because sphagnum mosses contain bactericidal substances. For this reason, dead sphagnum moss is continually built up at the bottom while the plant grows at the top. The dead parts are pressed more and more tightly together and, after many years, turn into peat. In this way sphagnum moss can help create ‘land’ where there was once open water in the bog. In many places the peat has been dug up by people and used as fuel.

    The leaves of sphagnum mosses are made up of two different types of cell. One type is ordinary plant cells that can carry out photosynthesis. The other type is special cells that can store water. When it is dry, these cells fill with air, and the moss will look white. When water returns, the cells fill up again and the plant regains its colour. Because they have these water-storage cells, sphagnum mosses can soak up water equivalent to 20 times their own weight (Bjerkely 2018). This water-storage ability can help prevent flooding when a lot of rain suddenly falls, because they soak up the water.

    Try taking a sphagnum moss and another moss. Dry both. Weigh them while they are dry. Place them in water for 5–10 min. Let them drip off a little and weigh again.

    Because sphagnum mosses contain an antiseptic substance that is bactericidal, they have over time been used for storing fish, vegetables and so on. They have also been used by women as sanitary towels during menstruation and as nappies for children. This use exploited both the antiseptic effect and the ability to soak up water. We can also use sphagnum moss as toilet paper when out on a tur, and to wash our hands after a toilet stop. And if you get an insect bite, rubbing the spots with damp sphagnum moss can be soothing.

    Peat and sphagnum mosses have over time been harvested in large quantities, both for fuel and, in our own times, because peat is a good soil improver and growing medium. Large quantities of peat-based compost are therefore sold in garden centres and nurseries. The problem is that it takes nature many years to build up layer upon layer of sphagnum moss, while it can be harvested very quickly (see the section on the importance of bogs).

, via Wikimedia Commons](Torvmose/Torvmose.jpg)

Sphagnum moss. Photo: Bernd Haynold, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons

Sphagnum moss. Photo: Gina Wigestrand

Next steps

• Bjørnemose — another moss
• Etasjemose — another moss
• Lakes, river systems and bogs — biotope
• Plants — the hub

Learn more

• Artsdatabanken — species, status, Red List
• SNL — Norwegian botany — encyclopaedic
• Sopp- og Nyttevekstforbundet — courses and checks
• Botanisk forening — Norwegian botany community