Japanese Royal Fern, Osmunda japonica
The Japanese Royal Fern or Japanese Flowering Fern (Osmunda japonica), is a fern in the genus Osmunda native to eastern Asia, including Japan, China, Korea, Taiwan, and the far east of Russia on Sakhalin. It grows in moist woodlands and can tolerate open sunlight only if in very wet soil.
It is a deciduous herbaceous plant which produces separate fertile and sterile fronds. The sterile fronds are spreading, up to 31.5 to 39.5 inches tall. The fertile fronds are erect and shorter, 8 to 20 inches tall. Like other ferns, it has no flowers, but rather elaborate sporangia, that very superficially might suggest a flower, from which the alternative name derives.