There’s more than meets the eye when it comes to lichen.
How many times have you passed by a rock face and noticed a colourful patch of crusted lichen? Or wandered the trails in Strathcona Park and marvelled at the strands of beard lichen (Usnea filipendula) hanging from tree limbs? Like me, you may have taken a close-up photograph of the intriguing lipstick lichen (Cladonia macilenta), with tiny, light-green fingers poking upright with a red dot on each end. Perhaps you’ve wondered about the array of lungwort at your feet, collected below old maple trees. But for all the lichen sightings you may have had, what do you really know about this intriguing life form? Read on—you may be surprised at what you discover.
Lichens vs mosses: The fungi-algae sandwich
First of all, lichens are not mosses. I like the Canadian Museum of Nature’s explanation: “In short, a moss is a simple plant, and a lichen is a fungi-algae sandwich.” A cross-section of lichen would show algae intermingled with fungal hyphae in a central core between upper and lower layers of fungus. At a higher magnification level, you’d also see cyanobacteria and yeast. That’s four species collaborating and providing each other with the elements needed for their survival: fungi scavenging for essential nutrients like nitrogen, and algae/bacteria photosynthesizing. This collaborative process is known as symbiosis.
Loys Maingon, a biologist living in the Comox Valley, describes lichens as an anomalous life form, since they don’t fit into the Linnaean model of classification. “There is nothing binary about lichens; they are organisms working together,” he says. He should know—he literally wrote the book on them.
A biologist’s insight into lichen species
His Field Guide to Basic Lichens of Strathcona Park was published in 2023. Maingon has observed over 330 species of lichen in Strathcona Park, and suspects that’s just half of the total number of species in the region. He hosts a lichen identification workshop each summer through the Strathcona Wilderness Institute where he shares his passion for this fascinating species.
Symbiosis among different species gets even more intriguing. Maingon explains that certain lichens need old growth to survive, and the old growth needs the nitrogen they produce. There is a suite of high nitrogen-producing lichens that are only found in forests more than a thousand years old. This statement gives me pause. It’s like an invitation to look for ways to embody symbiotic—rather than competitive—relationships.
Lichens as indicators of environmental change
Lichens play an important role for scientists observing and mapping changes in pH, air pollutants, and temperature related to environmental changes. Maingon shares an anecdote from Britain during the 1950s and 1960s. After the passing of the British Clean Air Act, schoolchildren were taught to identify and record their lichen observations as an inexpensive and effective way to monitor the effects of acid rain. As coal burning in Britain decreased, previously decimated lichen populations returned to former habitats. This was a cost-effective method of environmental monitoring that was also surprisingly accurate.
The often-overlooked lichen has a surprising variety of uses by humans around the world. Various cultures have used lichens for medicinal purposes, both in the past and present day. A few species of lichen are known to be edible on each continent. For example, some of the participants during Season 2 of Alone, on northern Vancouver Island, resorted to eating the lichen known as rock tripe (Umbilicaria) when other food sources could not be procured. Indigenous peoples around the world survive harsh winters and food scarcity by eating lichen species. Not all lichen is consumed during times of famine: in Japan and Korea, rock tripe is utilized as a delicacy in certain traditional dishes.
Lichens in textile production and dyeing
Many lichens can be used for textile production. In the Pacific Northwest, a prized species for dyeing raw fleece and fibre is staghorn lichen (Evernia prunastri). Although it’s pale green in the woods, it yields a lovely purple tone. Ethical harvesting is always recommended: harvest from deadfall and fallen trees only, as opposed to removing healthy, live organisms. I highly recommend Alissa Allen’s mycopigments website to learn more about the process and view some of the vibrant colours that lichens can produce.
The next time you’re out for a hike, or even a walk in the woods, take time to look for lichens. Investigate more closely and notice their colours, patterns of growth, and the surreal quality of worlds within worlds. Maybe, like me, you’ll become curious about their interconnectedness and find yourself reflecting on the delicate inter-relationships among species.
