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licorice fern, licorice polypody fern

California polypody

Stems

not whitish pruinose, slender to moderately stout, to 6 mm diam., intensely sweet, licorice-flavored;

scales concolored, brown or slightly darker near point of attachment, lanceolate to lanceolate-ovate, symmetric, margins entire.

dull or inconspicuously glaucous, moderately stout, to 10 mm diam., acrid or bland-tasting;

scales uniformly brown or slightly darker near point of attachment, lanceolate-ovate, symmetric, margins entire to erose.

Leaves

to 75 cm.

to 70 cm.

Petiole

usually slender, 0.5–2 mm diam.

usually slender, to 3 mm diam.

Blade

lanceolate-ovate to oblong, pinnatifid, widest near middle or just below, to 16 cm wide, herbaceous, rarely slightly leathery;

rachis sparsely scaly to glabrescent abaxially, puberulent adaxially;

scales linear, usually less than 3 cells wide.

deltate to lanceolate-ovate, pinnatifid, usually widest near base, to 20 cm wide, leathery to herbaceous;

rachis sparsely scaly to glabrescent abaxially, puberulent adaxially;

scales deltate to ovate, usually more than 10 cells wide.

Segments

linear to oblong, less than 12 mm wide;

margins serrate;

apex acute to attenuate;

midrib puberulent adaxially.

linear-lanceolate to oblong, usually less than 15 mm wide;

margins serrate;

apex widely obtuse to rarely attenuate;

midrib puberulent adaxially.

Sori

midway between margin and midrib or slightly closer to midrib, usually less than 3 mm diam., circular to oval when immature.

midway between margin and midrib or slightly closer to midrib, usually less than 3 mm diam., oval when immature.

Spores

less than 58 µm, verrucose, with surface projections less than 3 µm. 2n = 74.

less than 58 µm, verrucose, with surface projections to 3 µm. 2n = 74.

Venation

free.

weakly to conspicuously anastomosing, most segments containing several areoles, often forming 1 row.

Sporangiasters

absent.

absent.

Polypodium glycyrrhiza

Polypodium californicum

Phenology Sporulating late fall–spring. Sporulating early winter–spring.
Habitat Cliffs and rocky slopes along coasts, often epiphytic, on a variety of substrates Cliffs and soil on rocky slopes, on a variety of substrates but usually igneous
Elevation 0–700 m. (0–2300 ft.) 0–1500 m. (0–4900 ft.)
Distribution
from FNA
AK; CA; ID; OR; WA; BC; YT; Asia in Kamchatka in the former Soviet republics
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[BONAP county map]
from FNA
CA; Mexico in Baja California
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[BONAP county map]
Discussion

Polypodium glycyrrhiza hybridizes with P. calirhiza and with P. hesperium to produce sterile triploids with misshapen spores. Polypodium glycyrrhiza was involved in the origin of both of these allotetraploid species, and some individuals can be difficult to identify. Free versus anastomosing venation distinguishes this species from P. calirhiza; the presence of adaxial hairs on the rachis separates it from P. hesperium. An additional character for distinguishing these taxa is spore length, which is less than 58 µm in diploid P. glycyrrhiza and more than 58 µm in the two tetraploid species. Reports of P. glycyrrhiza occurring in Arizona (T. Reeves 1981; D. B. Lellinger 1985) are based on misidentified specimens.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

R. M. Lloyd and F. A. Lang (1964) recognized two cytotypes within Polypodium californicum. The tetraploid has proved to be an allopolyploid involving P. californicum and P. glycyrrhiza and is treated here as a separate species, P. calirhiza, following S. A. Whitmore and A. R. Smith (1991). Polypodium californicum can be confused with P. calirhiza, but it usually can be distinguished by blade shape, venation, spore size, and geographic distribution. D. S. Barrington et al. (1986) reported that spores of northern populations of P. californicum can be as large as those of P. calirhiza, but the former species has veins forming more areoles per segment than does the latter.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 2. FNA vol. 2.
Parent taxa Polypodiaceae > Polypodium Polypodiaceae > Polypodium
Sibling taxa
P. amorphum, P. appalachianum, P. californicum, P. calirhiza, P. hesperium, P. saximontanum, P. scouleri, P. sibiricum, P. triseriale, P. virginianum
P. amorphum, P. appalachianum, P. calirhiza, P. glycyrrhiza, P. hesperium, P. saximontanum, P. scouleri, P. sibiricum, P. triseriale, P. virginianum
Synonyms P. aleuticum, P. falcatum, P. occidentale, P. vulgare subsp. occidentale, P. vulgare var. falcatum, P. vulgare var. occidentale P. californicum var. kaulfussii, P. vulgare subsp. californicum, P. vulgare var. kaulfussii
Name authority D. C. Eaton: Amer. J. Sci. Arts ser. 2, 22: 138. (1856) Kaulfuss: Enum. Filic. 102. (1824)
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