cudweed; Gnaphalium japonicum
A small annual herb native to East Asia, often found in fields and roadsides. The name literally means 'father-and-child grass'.
Cudweed was blooming by the roadside.
Katakana spelling is common for plant names; usually written in kana.
Kanji spelling is rare; the plant is usually written in kana.
The name 父子草 (father-and-child grass) likely comes from the appearance of the flower heads, which resemble a parent and child together. The exact origin is uncertain.