Ontade

Ontade, (scientific name: Koenigia weyrichii var. alpinum) is an endemic species of Japan, and is a variant of the perennial "Urajiro tade" (scientific name: Aconogonon weyrichii) which is a perennial plant inthe family Polygonaceae. It grows naturally on sub-alpine to alpine gravel north of Chubu. Dioecious. In the summer, the flower stalk is put out, the panicles are extended from the shoot apex, and a number of light yellow florets bloom.
In fact, there are no petals and what looks like a flower is the calyx. The name of the flower is based on the first discovery at Mount Ontake in Kiso. On the back of the leaf of Urajiro tade(K. weyrichii ), white hair grows and looks whitish, while Ontade(var. alpinum) is green because it is hairless.

Generic name: Ontade, scientific name: Koenigia weyrichii var. Alpinum, Synonym: Aconogonon weyrichii var. Alpinum, Also: Iwatade, Plant height: 30 to 100 cm, leaf height: 10 to 20 cm, leaf shape: oval to long oval, with a sharp tip, Flowering period: June to October, flower diameter (actual calyx): 0.3 to 0.5 cm, Fruit type: thin.