Youngia denticulata or Yakushi-sou (scientific name: Youngia denticulata) is a two year wild grass of the genus Oncomybilaceae. It grows naturally in sunny fields and roadside throughout Japan in Hokkaido, Honshu, Shikoku and Kyushu. The stems are nonhairy, but there are red spots in some places. The leaves are elliptical in shape, with sawtooth on the leaf edge, attached alternately to the branches, hugging the stems at the base. In autumn, flower stalks are stretched out from well-branched flower stalks, and head flowers consisting only of yellow tongue-shaped flowers bloom. The flowers will face upwards, and after the flowers will fall downwards. Fresh leaves can be eaten. Although it is not the only name of this grass, it is also called Tsitsikusa (milk grass) because it is a white milky lot.
Common name: Youngia denticulata or Yakushi-sou, Scientific name: Youngia denticulata, Place of origin : East Asia such as Japan to China and Southeast Asia such as India and Indonesia, Distribution: All over Japan in Hokkaido, Honshu, Shikoku, Kyushu, Environment: sunny fields and roadside, plant height: 30 to 120 cm, leaf shape: oblong , Leaf margin: rough sawtooth, rough leaves: alternate, where flowers come out: axillary, flowering period: August to November, inflorescence: scattered inflorescence, corolla: head flower, flower color: yellow, flower diameter: 1.5 cm.