Feng Wei Cao

Pteris multifida, the spider brake or Chinese ladder brake, is a small evergreen fern of the Pteridaceae family forming dense tufts 30 to 70 cm tall. The slender stipes are straw-colored to dark brown at the base, smooth above. Fronds are dimorphic: sterile fronds are once-pinnate with broadly winged rachises and lanceolate to narrowly oblong pinnae with finely serrated margins, while fertile fronds are taller, more divided, with narrowly linear pinnae bearing continuous marginal sori protected by the reflexed leaf margin. The rhizome is short, creeping, and clothed in dark brown lanceolate scales. The species grows on shaded walls, limestone crevices, well-margins, and damp banks throughout China, Japan, Korea, the Himalayas, and parts of Southeast Asia, and is widely naturalized as a weed of greenhouses elsewhere.