Polypodium glycyrrhiza

Polypodium glycyrrhiza  Licorice Fern

Licorice ferns are the only commonly epiphytic species in the lowland forests of the Pacific Northwest.  Their rhizomes and roots are buried in the mosses and liverworts. The common name of this fern comes from the odor/taste of the rhizome.
http://ontarioferns.com/id/glossary/index.php is good for fern terms