Etymology
Greek: Blechnum is derived from the word blechnon, which is an ancient Greek word for ferns in general.
Description
Rhizome: erect to creeping, scales brown or black.
Frond: evergreen, dimorphic, fertile leaves more erect and longer than sterile leaves.
vascular bundles: more than 2 vascular bundles arranged in arc.
Blade: pinnatifid to 1-pinnate, ovate, leathery, young fronds are often red.
veins sterile:free, often forked; fertile: veins of fertile leaves united to form sorus-bearing secondary vein parallel to costa or costule.
Sori: elongate, continuous, on both sides of the costae, indusium: flap-like, opening towards the costa.
Distinctive Characteristics
Emerging fronds in the genus are usually red or reddish, loosing the color when fully expanded.
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Blechnum spicant. a) free venation in sterile pinna; b) netted venation of fertile pinna.
Illustration from Scandinavian Ferns by Benjamin Ĝllgaard and Kirsten Tind, Rhodos, 1993.
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Etymology
Named for Thomas Jenkinson Woodward, (1745-1820), an English botanist.
Description
Rhizome: long-creeping, scales.
Frond: deciduous, monomorphic or dimorphic.
Stipe: scaly or not, vascular bundles: variable.
Blade: pinnatifid to 1-pinnate-pinnatifid, thin-textured, scales on emergence in W. areolata, but glabrous later.
veins free or partly netted.
Sori: in chainlike rows, but distinct, along the costae, indusium: flap-like, opening towards the costa.
Distinctive Characteristics
Linear sori adjacent to the costae characterize Woodwardia.
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