Named after Nathaniel Wallich (1786-1854), British pteridologist
Rhizome: erect, massive, bearing several fronds in a whorl, sometimes producing offshoots, scaly.
Frond: 120 cm high by 20 cm wide, evergreen, monomorphic, blade/stipe ratio: 3:1 to 4:1.
Stipe: straw-colored or darker, grooved, scales on stipes lanceolate to ovate-lanceolate, to 2.5 cm long, acuminate at apex, black or very dark brown in Asian plants, mid-brown in Central America, vascular bundles: 3-7 in a c-shaped pattern.
Blade: 1-pinnate-pinnatifid, oblong-lanceolate, widest near the middle, stiff-papery, green to deep green, paler beneath, similar scales to stipe on rachis.
Pinnae: 20 to 35 pair, sessile; pinnules narrowly oblong, 5--8 mm broad, roundly truncate to round at apex; costae grooved above, continuous from rachis to costae; margins irregularly dentate; veins free, forked.
Sori: round, one medial row at each side of midribs of lobes, indusium: reniform, at a sinus, sporangia: brownish.
Habitat: humus-rich mountain slopes in shade at 1700-3000 m.
Distribution: from Mexico to Argentina, Zimbabwe, Madagascar, Turkey, east across all of Asia below southern China, Phillippines, Hawaii, i.e., anywhere in the subtropics or tropics with a mountain above 1700 m.
Hardy to -25°C, USDA Zone 5.
distinguished by narrow, dark (see above) scales, rectangular, regularly-spaced, lustrous pinnules, and conspicuous veins on the underside
Aspidium wallichianum Spreng
Dryopteris doiana Tagawa
Dryopteris paleacea (Sw.) C. Chr.
Aspidium parallelogrammum Kunze
Dryopteris filix-mas ssp. parallelogramma (Kunze) H. Christ
Lastrea filix-mas var. paleacea Moore
Nephrodium paleaceum Lowe
Illustration from The Cultivated Species of the Fern Genus Dryopteris in the United States, Barbara Joe Hoshizaki and Kenneth A. Wilson, American Fern Journal, 89, 1, (1999), with permission.