わが国の各地をはじめ、朝鮮半島や中国、ベトナムに分布しています。山地の林内に生え、高さは50〜80センチになります。茎は直立し、茎頂に「とちのき」に似た掌状複葉を輪生します。6月から8月ごろ、花茎を伸ばして球状の散形花序に黄緑色の花を咲かせます。根茎は竹節人参(ちくせつにんじん)と呼ばれ、健胃薬や去痰薬として用いられます。中国語では「竹節参(zhu jie shen)」と呼ばれます。
ウコギ科トチバニンジン属の多年草で、学名は Panax japonicus。英名はありません。
The "Tochiba-ninjin" (Panax japonicus) belongs to Araliaceae (the Ginseng family). It is a perennial herb that is found throughout Japan, as well as on the Korean Peninsula, in China, and in Vietnam. This herb grows in montane forests and can reach 50-80 cm in height. The stem is erect. The leaves are palmate compound, resemble the Japanese horse chestnut, and arranged in whorl on the stem apices. The globose umbels are borne bloom small yellowish-green flowers from June to August. The rootstocks are used as a herbal medicine for a stomachic agent or an expectorant drug. In Chinese, it is called "竹節参" (zhu jie shen).