Etymology
Stewartii is named for John Stuart, Earl of Bute (1713-1792)
Description
Rhizome: erect, branching.
Frond: 100 cm high by 35 cm wide, deciduous, monomorphic, blade/stipe ratio: 2:1 to 3:1.
Stipe: grooved, scales dark brown, vascular bundles: 3-7 in a c-shaped pattern.
Blade: 2-pinnate, lanceolate, herbaceous to somewhat leathery, linear to ovate scales below, absent above.
Pinnae: 20 to 22 pair, subopposite, lowest pinnae anadromic; pinnules slightly pinnatifid at the base, the first lower pinnule of the lowest pinnae slightly longer than the upper pinnule, basal pinnules stalked; costae grooved above, continuous from rachis to costae; margins spiny; veins free, forked.
Sori: round, 1-2 mm, medial, on both sides of the costule, indusium: reniform, tan, at a sinus, sporangia: brown to black, maturity: late spring to summer.
Culture
Habitat: in forests at mid to high elevations.
Distribution: Himalayas: Afghanistan, Pakistan, India, Nepal.
Hardy to -20�C, USDA Zone 6.
Synonyms
Dryopteris odontoloma f. brevifolia Mehra & Khullar
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Dryopteris stewartii.
�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.
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