In the depths of winter, an amazing emergence of emerald green ferns appear on cliffs, rocks, and forest tree trucks throughout the coast redwood forest. These delicate beauties are Polypodium glycyrrhiza, commonly known as licorice fern. The species name, glycyrrhiza, means sweet root in Greek and is aptly named because the fern’s rhizome tastes faintly of licorice.
In 2010, funded by Save the Redwoods League and the National Science Foundation, Professor Jarmila Pittermann and Burns began a study comparing the leaves of evergreen and deciduous ferns. Interested in their response to drought, they chose midsummer, just before the deciduous ferns would shed their leaves, in the drier southern part of coast redwoods’ range (in the Santa Cruz Mountains and Big Sur). They expected that evergreen leaves, which are thicker, would show fewer signs of water stress.