{{Short description|Species of fern}} {{Speciesbox | name = ''Osmunda japonica'' | image = Osmunda japonica leaf.jpg | image_caption = Sterile frond | genus = Osmunda | species = japonica | authority = Thunb. }}
'''''Osmunda japonica''''' (syn. ''Osmunda nipponica'' <small>Makino</small>), also called '''Asian royal fern'''<ref>{{Cite book |url=http://www.forest.go.kr/kna/special/download/English_Names_for_Korean_Native_Plants.pdf|title=English Names for Korean Native Plants |last=Korea National Arboretum |publisher=National Arboretum |year=2015 |isbn=9788997450985 |location=Pocheon |pages=556 |access-date=6 December 2016 |via=Korea Forest Service |url-status=dead |archiveurl=https://web.archive.org/web/20170525105020/http://www.forest.go.kr/kna/special/download/English_Names_for_Korean_Native_Plants.pdf |archivedate=25 May 2017}}</ref> or '''fiddlehead''', is a fern in the genus ''Osmunda'' native to east Asia, including Japan, China, Korea, Taiwan, and the far east of Russia on the island of Sakhalin. It is called ''gobi'' ({{lang|ko|고비}}) in Korean, ''zenmai'' ({{lang|ja-Hrkt|{{linktext|ゼンマイ}}}}; {{lang|ja-Hani|薇}}) in Japanese, and ''zǐqí'' or ''juécài'' ({{lang|zh|{{linktext|紫萁}}}} or {{lang|zh|{{linktext|蕨菜}}}}) in Chinese.<ref name="GRIN">{{GRIN}}</ref>
It is a deciduous herbaceous plant which produces separate fertile and sterile fronds. The sterile fronds are spreading, up to 80–100 cm tall, bipinnate, with pinnae 20–30 cm long and pinnules 4–6 cm long and 1.5–2 cm broad; the fertile fronds are erect and shorter, 20–50 cm tall.
It grows in moist woodlands and can tolerate open sunlight only if in very wet soil. Like other ferns, it has no flowers, but rather elaborate sporangia, that very superficially might suggest a flower, from which the alternative name derives.
Like its relative ''Osmundastrum cinnamomeum'' ("cinnamon fern"), the fertile fronds become brown-colored and contain spores. The sterile (vegetative) fronds resemble those of ''Osmunda regalis'' ("royal fern"), another relative of ''O. japonica''.
In some parts of China, Tibet, and Japan, the young fronds or fiddleheads of ''O. japonica'' are used as a vegetable.<ref>{{cite journal |pmid=25973486 |year=2015 |last1=Dion |first1=C |title=Evaluation of the anti-inflammatory and antioxidative potential of four fern species from China intended for use as food supplements |journal=Natural Product Communications |volume=10 |issue=4 |pages=597–603 |last2=Haug |first2=C |last3=Guan |first3=H |last4=Ripoll |first4=C |last5=Spiteller |first5=P |last6=Coussaert |first6=A |last7=Boulet |first7=E |last8=Schmidt |first8=D |last9=Wei |first9=J |last10=Zhou |first10=Y |last11=Lamottke |first11=K |doi=10.1177/1934578X1501000416 |s2cid=8419285 |doi-access=free }}</ref> In Korea too, these young shoots are commonly used to make dishes like ''namul''.<ref>{{citation|last1=Pratt |first1=Keith |last2=Rutt |first2=Richard |title=Korea: A Historical and Cultural Dictionary |publisher=Routledge |year=2013 |url=https://books.google.com/books?id=8tdcAgAAQBAJ&pg=PA310 |page=310 |isbn=9-781-1367-9400-1}}</ref>
''O. japonica'' has also been shown to improve indoor air quality by significantly reducing of air toxins, specifically formaldehydes.<ref>{{Cite journal |last=Claudio |first=Luz |date=October 2011 |title=Planting Healthier Indoor Air |journal=Environmental Health Perspectives |volume=119 |issue=10 |pages=a426–a427 |doi=10.1289/ehp.119-a426 |issn=0091-6765 |pmc=3230460 |pmid=22069776}}</ref>
<gallery mode="packed" heights="160px"> File:Osmunda japonica 002.jpg|Young frond in spring File:紫萁 20190526173645.jpg|Young plant </gallery>
==References== {{Reflist}}
==External links == {{Commons category|Osmunda japonica}} * {{PFAF|Osmunda japonica}} * [https://web.archive.org/web/20090505213204/http://tai2.ntu.edu.tw/udth/bin/fot1.exe/browse?bid=1&page=82 Flora of Taiwan: ''Osmunda japonica''] * [http://www.biomedsearch.com/attachments/00/23/59/70/23597086/1746-4269-9-28.pdf Eating from the wild: diversity of wild edible plants used by Tibetans in Shangri-la region, Yunnan, China] {{Webarchive|url=https://web.archive.org/web/20140812040959/http://www.biomedsearch.com/attachments/00/23/59/70/23597086/1746-4269-9-28.pdf |date=2014-08-12 }}
{{Taxonbar|from=Q23363}} {{Authority control}}
{{DEFAULTSORT:Osmunda japonica}} Category:Osmundales Category:Ferns of Asia Category:Flora of China Category:Flora of Eastern Asia Category:Flora of Sakhalin Category:Flora of Japan Category:Flora of Korea Category:Flora of Tibet Category:Flora of Russia Category:Flora of Taiwan Category:Ferns of China Category:Ferns of Japan Category:Ferns of Korea Category:Ferns of Tibet Category:Ferns of Russia Category:Ferns of Taiwan Category:Plants described in 1780
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