When I first spotted this thing from a distance, growing on a birch tree in southwestern British Columbia, I assumed it was a kind of ivy. But when I got up close to it, I realized that each leaf had its own unique shape. I had to know what it was and how I could get some for my woodland garden.
Lungwort pulmonaria growing on the right trunk of a forked birch tree in a garden near Harrison Lake in southwestern British Columbia.
After a little digging, I was surprised to discover that it wasn’t a vine at all but a lichen and, not only that, this lichen is actually a symbiotic relationship between a fungus and two algae. So, basically, three entities getting together to make an awesome leafy thing. The lichen goes by the ponderous moniker of Lungwort pulmonaria, inspired by the idea that the ‘leaves’ resemble the tissue of lungs. Understandably.
I found this lungwort (above) growing along a branch on a tree in a park on Vancouver Island.
Lungworts are called foliose lichens because they have that distinctively leafy characteristic. They’re usually found growing on the bark of mature deciduous trees in untouched forests. So chances are you’re not going to find them in an urban backyard as they can’t tolerate air pollution and prefer old, dense woodland.
Close-ups of the lungwort I found by Harrison Lake.
England’s Woodland Trust identifies lungwort lichens as an ancient woodland indicator. That explains why I found two lovely examples in British Columbia (home of temperate old growth rain forests) and why I’ve never seen them in southern Ontario where actual always-been-there forests have virtually disappeared. They also prefer ancient woodlands that are humid, shady and at a low-elevation–again, loving the temperate rain forests.
Interestingly, these lichens don’t harm the trees they grow on. Instead, they’re multi-tasking in really good ways. They provide shelter and food for small insects which in turn feed birds and other, bigger insects. They also play a part in carbon cycling and water retention.
By scientific standards, a Lungwort lichen isn’t a single entity. Instead, it’s considered a community. A multi-species community. They’re a wonder of the natural world but the partnership they have isn’t too dissimilar from other beneficial symbiotic relationships such as:
- Mycorrhiza, found in/on plant roots helping the plant to transfer water and minerals from the soil to the plant while the plant supplies the fungus with sugars manufactured through photosynthesis
- the resident bacteria in our own guts which aid in our digestion among other wonderful things
I’d love to introduce some of these beauties (the lichen, not the gut bacteria) into my woodland garden but I understand now that’s impossible. And just as well, I suppose. Some things are meant to be undisturbed and simply respected for their humble awesomeness.
But I had to share a little bit about them anyways.