Etymology
Alexander Carl Heinrich Braun, 1805-1877, German professor of botany.
Description
Rhizome: short, stout, erect, very scaly.
Frond: 70 cm high by 22 cm wide, evergreen, monomorphic, blade/stipe ratio: 4: 1 to 6:1.
Stipe: grooved, scales silvery at first, then light brown, dense at base, vascular bundles: 5-7, in an arc.
Blade: 2-pinnate, ovate, broadest at the middle, tapered gradually to the base, the lowest pinnae only 2 cm long, dull, dark green, leathery, rachis scales linear, straw-colored, lamina with whitish to brown narrow scales on both sides.
Pinnae: 20 to 40 pair, oblong; pinnules short-stalked, eared near the rachis, adnate further out, the first upper pinnule the same size or only slightly larger than the next ; margins edges toothed, with slender spiny tips; veins free, forked, anadromic.
Sori: round, distinct and separate, in 1 row between midrib and margin, sparse, indusium: peltate, light brown, shriveling in maturity, central, sporangia: gray-brown to black, maturity: midsummer to later.
Culture
Habitat: cool, moist, shaded places in boreal forests and northern deciduous woods; also rocky slopes and moist cliffs.
Distribution: North America, Europe, Asia.
Hardy to -35°C, USDA Zone 3.
Distinctive Characteristics
Similar in many respects to P. aculeatum, but the very small pinnae at the base are distinctive. This is also a larger plant with more fronds, a softer, duller lamina
Synonyms
Aspidium braunii Spenner
Polystichum braunii subsp. purshii (Fernald) Calder & Roy L. Taylor
Polystichum braunii var. purshii Fernald
Dryopteris braunii (Spenner) Underwood
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