どろのき (泥の木) [Index] [Back] わが国の本州中部地方以北から北海道、千島列島やサハリン、カムチャッカそれに朝鮮半島、中国の北中部、シベリアに分布しています。山地の水湿地や河畔林に生え、高さは１５〜３０メートルになります。樹皮は若い木では緑白色、老木になると暗灰色になります。若い木の表面は滑らかで菱形の皮目が散在しますが、老木になるにつれ縦にひび割れが入ります。葉身は広楕円形で、縁には鋸歯があり、裏は淡い緑白色で葉脈が突出します。雌雄異株で、４月から６月ごろ、葉の展開前に開花します。種子にはヤナギの仲間と同様に綿毛があり、風や水の流れを利用して散布されます。中国語では「甜楊（tian yang）」と呼ばれます。  ヤナギ科ヤマナラシ属の落葉高木で、学名は Populus suaveolens。英名は Japanese poplar。  The Japanese poplar (Populus suaveolens) belongs to Salicaceae (the Willow family). It is a tall deciduous tree that is distributed from the central region of Honshu northwards to Hokkaido in Japan, as well as the Kuril Islands, Sakhalin, Kamchatka, the Korean Peninsula, north-central China and Siberia. It grows in mountain wetlands and riparian forests, and can reach heights of 15 to 30 m. The bark is greenish-white on young trees, but becomes dark gray on older trees. The surface of young trees is smooth, with diamond-shaped lenticels scattered across it, but as the tree ages, it develops vertical cracks. The leaf blade is broadly elliptic, with serrated edges, and the underside is light greenish-white with prominent leaf veins. It is dioecious, and flowers from April to June before the leaves have fully developed. The seeds have woolly hairs like those of other willow species, and are dispersed by wind and water currents. In Chinese, it is called "甜楊" (tian yang).  茨城県つくば市「つくば実験植物園」にて、2024年10月13日撮影。  Shu Suehiro shu@botanic.jp