Lygodium japonicum (Thunberg ex Murray) Sw.

Japanese climbing fern

Etymology Japonicum refers to Japan.
Description Rhizome: short-creeping, branching, short, blackish hairs.
Frond: 300 cm high , but can be much more, deciduous, somewhat dimorphic, the fertile pinnae (in upper part of frond) narrowed, blade/stipe ratio: 30:1.
Stipe: twining, pale brown, lustrous, 10-30 cm, vascular bundles: 1, a simple cylinder.
Blade: 3-pinnate or more, twining rachis, 2-pinnate pinnae, papery, short, curved hairs on both blade surfaces.
Pinnae: alternate, a pair of 2-pinnate segments, less than 20 cm long; costae densely hairy above and sparsely so below, distinctly winged; segments lanceolate, lobed; fertile segments fringed; veins free, forking, ending in marginal teeth.
Sori: , indusium: false, pear-shaped scale, sporangia: in 2 rows, below the margin, maturity: late summer to early winter.
Culture Habitat: thickets in low mountains. Distribution: Japan, Korea, China. Hardy to -15°C, USDA Zone 7.
Distinctive Characteristics twining habit
Synonyms
Ophioglossum japonicum Thunb.
Adiantum scandens Lour.
Hydroglossum japonicum (Thunb.) Willd.
Lygodium scandens (L.)Sw.
Lygodium japonicum
Lygodium japonicum. Pinnae and fertile segment.  Illustration by Edgar Paulton, from How to Know the Ferns and Fern Allies, John T. Mickel, © 1979 Wm. C. Brown Co.
Notes
Morphology The Flora of North America disagrees with the above from the Flora of Japan, omitting hairs oon the costa, rachis, and upper surface, and the winged costae.

Lygodium japonicum. Fertile pinnae. Hawaii.  Photo by Forest & Kim Starr (USGS)
Lygodium japonicum
Lygodium japonicum. Sterile and fertile pinnae.  Photo © Shirley Denton, from her web site, with permission.
Lygodium japonicum
Lygodium japonicum. Fertile pinna.  Copyright © 2008 by Robbin Moran
Valid XHTML 1.0     Reports of errors and omissions appreciated: toms AT hardyfernlibrary.com (please replace the AT with @)