Herbaceous aster with tiny white petals with teeth on the outer margin and lance-ovate leaves.
may be ハキダメギク.
North american weed.
1 I know this
Aka: Peruvian Daisy
Galinsoga quadriradiata aka shaggy soldier, quickweed, hairy galinsoga is a fast-growing annual herb that belongs to the Asteraceae family. The petioled leaves are oval, coarsely toothed and sparsely to densely hairy. The small flower has 5 white ray oval florets with deep notches in the end. The center disk flowers are golden yellow. The ray and disk produce a dry seed with narrow scales and each scale has an awn at the tip.
Galinsoga quadriradiata is a species of flowering plant in the daisy family which is known by several common names, including shaggy soldier, hairy galinsoga, and fringed quickweed. It is found throughout most of the temperate world, but apparently its native home is Mexico. In Portuguese-speaking countries where it is widely naturalized - e.g. in Brazil - it is known as botão-de-ouro. As an agricultural weed it can reduce crop yields by up to 50%.