Asanoha Maple - Asanoha Maple

A deciduous tree of the maple family (APG classification: Sapindaceae). The leaves grow in pairs. The petiole is 3-10 cm long, the leaf blade is 6-10 cm long and wide, and has 5 palmate lobes with double serrations on the leaf margins. The leaf shape is somewhat similar to that of hemp. The winter buds have two pairs of scales. Dioecious. The flowers are small, pale green-yellow, and about 10 flowers form a raceme (female inflorescence) or an umbel-shaped raceme (male inflorescence), which opens around May. There are four petals, sepals, and stamens. The fruit has two wings and ripens in autumn. It is distributed in the temperate mountainous areas of Honshu and Shikoku west of Fukushima Prefecture, and is often found in the lower parts of mountains and in moist areas along streams. There are four closely related species in Korea, China, and the Himalayas.

[Ken Ogata September 17, 2020]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

カエデ科（APG分類：ムクロジ科）の落葉小高木。葉は対生する。葉柄3～10センチメートル、葉身は長さ、幅ともに6～10センチメートルで掌(しょう)状に5中裂し、葉縁に重鋸歯(じゅうきょし)がある。葉形はややアサの葉に似る。冬芽の鱗片(りんぺん)は2対。雌雄異株。花は淡緑黄色の小花で、約10花が総状花序（雌花序）または散形状総状花序（雄花序）をなして、5月ごろ開く。花弁、萼片(がくへん)、雄しべとも4個。果実は2翼あり、秋に熟す。福島県以西の本州、四国の温帯山地に分布し、山腹下部や沢沿いの湿潤地に多い。近縁種が朝鮮、中国、ヒマラヤにかけて4種ある。

［緒方　健　2020年9月17日］

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