Boreal felt lichen: “Lichening” a declining fungus to human health risks.

Photo by Christoph Scheidegger |

Photo by Christoph Scheidegger |

This week, we're shining the spotlight on Canada's most threatened flora and fauna; the ones that are at risk of no longer blooming, crawling, or running within our borders. Climate change, pollution, and habitat destruction are just some of the anthropogenic factors contributing to declining numbers of these plants and animals. Here, we reflect on the importance of species diversity, and what people like you and I can do to help maintain ecological integrity within Canada. 

Common Name: Boreal Felt Lichen

Scientific Name: Erioderma pedicellatum

Where in Canada: Newfoundland

IUCN Status: Critically Endangered

What do Norway, Sweden, and Newfoundland have in common? Erioderma pedicellatum! You probably thought I was going to say Vikings, which is totally true, but I’m talking about a species of fungi commonly known as Boreal Felt Lichen.

Sadly, this species of lichen is headed in the same direction as our Norse ancestors. As of 2003, The International Union for Conservation of Nature (IUCN) currently lists Boreal Felt Lichen as a critically endangered species, and it is already regionally extinct in Norway, Sweden, and New Brunswick; only in Newfoundland has a considerable regional population survived, where 5,060 individuals (called “thalli”) have been documented. The only other region with documented E. pedicellatum is Nova Scotia, where 14 thalli are known.

Boreal felt lichen gets its name from its fuzzy, felt-like appearance. It primarily grows on coniferous trees in old growth forests along the Atlantic coast. In Norway, E. pedicellatum grew on twigs of Norway spruce and in Newfoundland it primarily makes itself at home on the trunks of balsam fir trees. The specific habitat requirements of E. pedicellatum, in combination with its low growth and reproductive rates, are contributing factors to its decreasing population.

Other major contributors to the critically endangered status of E. pedicellatum include logging and its sensitivity to atmospheric air pollutants such as acid rain and industrial emissions. Lichen are unable to avoid the accumulation of pollutants because they do not have roots like plants do; rather, they absorb all of their nutrients (and pollutants!) from the air.

While this can be detrimental to the lichen, it is a very exciting attribute for scientists and citizens interested in tracking air quality in their community. For example, tree lichen monitoring is used in Hamilton, Ontario as one way to deal with local pollution concerns resulting from industrial emissions. Relying on the relationship between ambient air quality levels and two species of tree lichen, lichen tree monitoring consists of using a simple measuring tool to visually identify and gauge the presence of Candelaria concolor and Physcia millegrana on both maple and ash trees.

In short, the more of these species of lichen present, the better the area’s air quality. To learn more about this project visit Environment Hamilton’s Good Neighbour Campaign page and discover how you can apply this technique in your own neighbourhood and engage with your community about these important issues.  

Tree lichen monitoring is a project that illuminates the importance of conserving the lichen population in Canada and protecting our own health and well-being. While the decline of E. pedicellatum is considered irreversible, we all have a part to play in conserving endangered species here in Canada. Perhaps we ought to consider the impact of pollutants on tree lichen, and think about what those same pollutants are doing to our own bodies. So think twice about your consumption habits, put pressure on local industries to reduce emissions, and respect your fungi friends as you respect each other!

You can learn more about species in Canada on the IUCN Red List by searching here.