Licorice fern • Polypodium glycyrrhiza
Heiltsuk/Haíɫzaqv - k̓áláx • Nuxalk - k'tsaatsay
Upper left and right photos: The underside of licorice fern leaves growing from a mossy tree trunk on Calvert Island. The visible spots are the sori, which contain sporangia (see below). Photos by ES470 students. Lower left: licorice fern leaves growing from mossy ground. Photo by Stuart Higgs.
Identification
Licorice fern is most easily distinguished by the single leaves that grow from various points along a reddish-brown rhizome. This is in contrast to other ferns, where several leaves grow from a single spot. Licorice fern leaves may form large mats over rocks or trees, but each leaf will originate separately.
Note that the right photo, above, shows only a single leaf, with the smaller parts called leaflets. The leaflets of licorice fern are attached all the way along their margins to the stipe (stem), and are usually longer than 3cm (~1").
Licorice fern leaflets may have rust-brown spots on their undersides. There are two rows on each leaflet. These are sori, the structures that contain sporangia. Sporangia produce and store spores, which is how the fern reproduces, which are then released. For more on fern reproduction, click here.
Habitat & Range
Licorice fern is commonly found as an epiphyte on trees (as in upper left and right photos, above), although it does also grow on the ground and on fallen trees. The species prefers wet, mossy substrates and is generally found at low elevations.
Licorice fern is generally a coastal species, ranging from southeast Alaska to California, and occuring inland through Washington, Oregon, and Idaho. There is also a disjunct (unattached) population in Arizona.
Similar Species
There are several very similar species of Polypodium along the coast. Licorice fern is the only one with a flavoured rhizome, but if you are not about to dig one out and taste it, there are some other ways to identify the various species. Leathery polopody (P. scouleri) is found almost exclusively where salt spray reaches, and has much more leathery leaflets than licorice fern, and rounded leaflet ends. Pacific or irregular polypody (P. amorphum) has shorter leaflets with rounded tips, and a bitter rhizome. Finally, western polypody (P. hesperium) is a hybrid of licorice fern and Pacific polypody, and as such has a licorice-flavoured rhizome, but rounded leaflets.
Other similar species one is likely to encounter include deer fern (Blechnum spicant), but the leaves of deer fern arise from a single location, unlike licorice fern. Small sword fern (Polystichum munitum) is also similar-looking, but the leaflets are attached to the stipe by small stems, rather than the entire margin of the leaflet. The leaves of sword fern will also originate in the same spot and form a crown.
Human Uses
Licorice fern is one of the few ferns that was consumed by Indigenous Peoples throughout their range. Specifically, people used the licorice-flavoured rhizomes. Some Peoples used them as a medicine for sore throats and colds or as a sweetener in bitter medicines, while others, including the Squamish, Sechelt, Comox, Nuxalk, Haida and Kwakwaka'wakw, chewed them for the licorice flavour. The Upper Coquelle boiled them and drank the licorice-flavoured water.
iNaturalist
https://www.inaturalist.org/taxa/55104-Polypodium-glycyrrhiza
Licorice fern is most easily distinguished by the single leaves that grow from various points along a reddish-brown rhizome. This is in contrast to other ferns, where several leaves grow from a single spot. Licorice fern leaves may form large mats over rocks or trees, but each leaf will originate separately.
Note that the right photo, above, shows only a single leaf, with the smaller parts called leaflets. The leaflets of licorice fern are attached all the way along their margins to the stipe (stem), and are usually longer than 3cm (~1").
Licorice fern leaflets may have rust-brown spots on their undersides. There are two rows on each leaflet. These are sori, the structures that contain sporangia. Sporangia produce and store spores, which is how the fern reproduces, which are then released. For more on fern reproduction, click here.
Habitat & Range
Licorice fern is commonly found as an epiphyte on trees (as in upper left and right photos, above), although it does also grow on the ground and on fallen trees. The species prefers wet, mossy substrates and is generally found at low elevations.
Licorice fern is generally a coastal species, ranging from southeast Alaska to California, and occuring inland through Washington, Oregon, and Idaho. There is also a disjunct (unattached) population in Arizona.
Similar Species
There are several very similar species of Polypodium along the coast. Licorice fern is the only one with a flavoured rhizome, but if you are not about to dig one out and taste it, there are some other ways to identify the various species. Leathery polopody (P. scouleri) is found almost exclusively where salt spray reaches, and has much more leathery leaflets than licorice fern, and rounded leaflet ends. Pacific or irregular polypody (P. amorphum) has shorter leaflets with rounded tips, and a bitter rhizome. Finally, western polypody (P. hesperium) is a hybrid of licorice fern and Pacific polypody, and as such has a licorice-flavoured rhizome, but rounded leaflets.
Other similar species one is likely to encounter include deer fern (Blechnum spicant), but the leaves of deer fern arise from a single location, unlike licorice fern. Small sword fern (Polystichum munitum) is also similar-looking, but the leaflets are attached to the stipe by small stems, rather than the entire margin of the leaflet. The leaves of sword fern will also originate in the same spot and form a crown.
Human Uses
Licorice fern is one of the few ferns that was consumed by Indigenous Peoples throughout their range. Specifically, people used the licorice-flavoured rhizomes. Some Peoples used them as a medicine for sore throats and colds or as a sweetener in bitter medicines, while others, including the Squamish, Sechelt, Comox, Nuxalk, Haida and Kwakwaka'wakw, chewed them for the licorice flavour. The Upper Coquelle boiled them and drank the licorice-flavoured water.
iNaturalist
https://www.inaturalist.org/taxa/55104-Polypodium-glycyrrhiza
References
A Brief Introduction to Ferns. The American Fern Society. Accessed on 06/04/2013.
Pojar, J. and MacKinnon, A. (2005). Plants of Coastal British Columbia, Revised. Vancouver, BC: Lone Pine Publishing. P. 424.
(2012). Licorice fern. Notes on ethnobotany in western Oregon. Accessed 06/04/2013.
Polypodium glycyrrhiza D.C. Eaton. licorice fern. In Klinkenberg, Brian. (Ed.). E-Flora BC: Electronic Atlas of the Plants of British Columbia. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. Accessed on 03/04/2013.
Authors and editors of page
Chanda Brietzke and Brian Starzomski (2013).
A Brief Introduction to Ferns. The American Fern Society. Accessed on 06/04/2013.
Pojar, J. and MacKinnon, A. (2005). Plants of Coastal British Columbia, Revised. Vancouver, BC: Lone Pine Publishing. P. 424.
(2012). Licorice fern. Notes on ethnobotany in western Oregon. Accessed 06/04/2013.
Polypodium glycyrrhiza D.C. Eaton. licorice fern. In Klinkenberg, Brian. (Ed.). E-Flora BC: Electronic Atlas of the Plants of British Columbia. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. Accessed on 03/04/2013.
Authors and editors of page
Chanda Brietzke and Brian Starzomski (2013).