What is an epiphyte?
An epiphyte is a plant that grows on other plants (but is not parasitic), and therefore gets its nutrients from moisture and nutrients in the air, rain, and debris. Many epiphytes are found in jungles and rainforests and are called “air plants,” including orchids. In Bridle Trails our epiphytes include licorice fern, liverworts, lichens and a number of mosses.
Licorice Fern
Ferns grow quickly and happily in the Pacific Northwest, and Bridle Trails State Park is home to 8 species. Licorice fern is a fern that is commonly found growing on bigleaf maples and red alders, as well as logs, rocks, and the ground.
The rhizome (roots) of this evergreen fern taste like licorice and trails along the surface of trees or other surfaces, usually hidden under moss. Licorice ferns shrivel up during hot, dry weather, appearing dead, but sprout new green fronds with the fall rains.
Licorice ferns were an important medicinal plant for many Native American tribes as well as old European cultures. The rhizomes were used as medicine against colds, coughs, and sore throats.
Moss
Moss is considered the “amphibian of the plant world” because they were the first plant life forms to develop out of water. Moss communities are much more complex than most people realize, with hundreds of thousands of species on almost every continent.
As Robin Wall Kimmerer eloquently states in Gathering Moss:
“Learning to see mosses is more like listening than looking. A cursory glance will not do it. Starting to hear a faraway voice or catch a nuance in the quiet subtext of a conversation requires attentiveness, a filtering of all the noise, to catch the music. Mosses are not elevator music; they are the intertwined threads of a Beethoven quartet.”
Many mosses are extremely drought resistant and can go dormant – they nearly completely dry out and are able to rehydrate when water is abundant again.
Epiphytes and Maple Trees
Maple trees have been documented as having the greatest epiphyte to shoot biomass ratio of Pacific Northwest forests; meaning there is a high mass of epiphytes living on the branches and bark of maple trees (sometimes up to 80 pounds!).
With this added surface area of branching mosses and ferns, maples are able to collect more rainwater and other nutrients from the air. Since mosses act like sponges, they also help each other stay moist during dry months. Research in the Pacific Northwest has revealed that bigleaf maples send roots into the epiphytes, taking in water and nutrients that way. Take a look on your next walk through the park for these moss-covered trees!
More information:
For a beautiful natural history book, read Gathering Moss by Robin Wall Kimmerer.
Check out this informative Living with Mosses website created by students at Oregon State University.
The Slater Museum of Natural History has more information on licorice ferns and other native PNW plants and animals found at Bridle Trails.
IslandWood has a 50 Days of Discovery page for sphagnum moss and bracken fern.
Bridle Trails State Park plant overview and species list here.
Photo Credits: Oregon Live, H. Rutherford.