Ontade (Alpine Knotweed)
Aconogonon weyrichii var. alpinum
Family: Polygonaceae / Genus: Aconogonon / Perennial herb
Height: 20–80 cm Flower color: White Blooming season: Early July – Late August
It is dioecious (male and female plants separate). The Japanese name means “a kind of smartweed found abundantly on Mt. Ontake in Kiso.”
Distribution: Restricted roads, Ken-ga-mine trail, along Echo Line and Skyline
Note: If you are lucky, you may see rock ptarmigans (raichō) pecking at it.