Ask An Expert: What Makes Icelandic Moss So Special?

We turned to an ecology professor for answers

Icelandic Moss is frequently advertised for its high nutritional value and health benefits. People love to slap the name on their cooking herbs or cough pastilles to make sure you know that you’re getting the real good stuff into your system. But what’s so special about that pillowy green stuff anyways? We went to Professor of Ecology, Ingibjörg Svala Jónsdóttir, of the University of Iceland, to learn more about what makes it special and that – gasp! – Icelandic moss is not actually moss!

“What is called ‘Icelandic Moss’ in English is actually a lichen,” Ingibjörg explains. “It’s a very common lichen here and one of the few, if not the only, that has been consumed by humans as a source of carbohydrates and also for health benefits – more or less because it is a good source of energy.”

“Together they build a very tough organism that can better tolerate harsh conditions such as high degrees of desiccation and low temperatures.”

The lichen – known as Cetraria islandica, Fjallagrös or even “True Icelandic Lichen” – has long been called a moss in English. “There is technically a distinction in English,” Ingibjörg clarifies. “You have the term ‘bryophytes,’ which include mosses, and then you have lichens. The common name adopted for this species of lichen is ‘Icelandic Moss’ and that has been used particularly in tourist brochures and when new products are launched that are made from these lichens.”

At this point it’s hard to say whether the mossy labelling originates from a translation issue (the blanket term in Icelandic is “mosi”) or because of the lichen’s moss-like appearance. But don’t let appearances fool you – moss and lichen are very different. Unlike moss, a lichen is not a single organism but a symbiosis with a fungus and different bacteria and sometimes green algae.

“Symbiosis means that two or more organisms are working closely together,” Ingibjörg elaborates. “In the case of lichens, they are so close that we view them more or less as one single organism, even though they are this combination of two or more. The fungi get organic compounds from the photosynthesis by the photobiont, whether it’s algae or bacteria, in exchange for shelter and nutrients and protection from harmful UV radiation.”

“Together they build a very tough organism that can better tolerate harsh conditions such as high degrees of desiccation and low temperatures.” That explains why it can survive in the more extreme environments and not even just here. “Cetraria islandica grows around the northern hemisphere, including in the Arctic, where it is an important food source for reindeer, and in alpine areas of the Rocky Mountains, the Appalachian Mountains, Wales, England and Scotland.”

The lichen is a source for carbohydrates, for example when cooked in milk to make fjallagrasamjólk, and has medicinal properties. “The lichen produces different chemicals, some are antibiotic or have antibiotic functions to different extents,” Ingibjörg says.

So best be careful not to step on the precious greenery, as it’s also very slow growing. According to Ingibjörg, “mosses, which are for example covering lava fields – yes, that is moss, not lichen – are very sensitive to trampling. Particularly when they are dry. Lichens that often grow within this moss – sometimes also within some other vegetation – also become very brittle when they are dry.”

Given that the lichens and moss have a significant impact on the ecosystems, carbon fluxes and the circulation of nutrients, and serve as strong indicators of the system’s health, it’s important to be careful with them. Plus, we’ve sort of taken a lichen to them.