Bulblet nettle - Bulblet nettle

A perennial plant of the Urticaceae family (APG classification: Urticaceae). The whole plant has stinging hairs like nettles, and in autumn it produces bulbils in the leaf axils, hence the name, but it is not a member of the Urticaceae genus, but rather a member of the Bulbule Urticae genus. The stem is 30-100 cm tall. It is usually unbranched. The leaves are alternate, long-stalked, and long-ovate. They are 5-18 cm long excluding the stalk. They have a circular base and serrated edges. The inflorescences grow in the leaf axils in summer and are cone-shaped. There are male and female varieties; male inflorescences are stalkless and grow in the middle leaf axils, while female inflorescences have long stalks and grow out from the upper leaf axils, rising high up. They grow in the mountain forests from Hokkaido to Kyushu, and are widely distributed outside of Japan in eastern and southern Asia. Their Chinese name is Bulbule Urticae. There are nearly 30 species in the Urticaria genus that are distributed mainly in the tropics, and two species are found in Japan: this species and the mountain nettle.

[Hiroshi Yonekura December 13, 2019]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

イラクサ科（APG分類：イラクサ科）の多年草。植物体全体にイラクサと同様の刺毛があり、秋に葉腋(ようえき)にむかごをつくるのでこの名があるが、イラクサ属ではなく、ムカゴイラクサ属である。茎は高さ30～100センチメートル。普通、枝分れしない。葉は長い柄(え)があって互生し、長卵形。長さは柄を除き5～18センチメートル。基部は円形となり、縁(へり)には鋸歯(きょし)がある。花序は夏に葉腋から出て円錐(えんすい)状。雌雄の別があり、雄花序は柄がなくて中部の葉腋につき、雌花序は長い柄があって上部の葉腋から出て高くぬけ出る。北海道から九州の山地の林内に生え、国外では東・南アジアに広く分布する。中国名は珠芽艾麻。ムカゴイラクサ属は30種近くが熱帯を中心に分布し、日本には本種とミヤマイラクサの2種が産する。

［米倉浩司　2019年12月13日］

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