Great St. Johnswort

Great St. Johnswort (Scientific name: Hypericum ascyron) is a cold-resistant perennial grass of the family Hypericaceae native to Japan. It grows naturally in grasslands and riverbeds. The stem is hairless and has four ridges. The leaves are needle-shaped, with opposite living, hugging the stem at the base. In the summer, the upper part of the stem is branched, 2 the outcropping inflorescences are extended, and five petals like bunches of five yellow bamboos (shaped like a comma) bloom. Flowers are flowers all day.
Although it is a plant which is not alike,Prickly Umbrella(scientific name: Wercklea ferox) makes flowers bloom in a bamboo shape.

Common name: Great St. Johnswort, Scientific name: Hypericum ascyron, aka: Great St. Johnswort, Hypericum ascylon, Origin: Japan, Leaf shape: oblong shape to needle shape, leaf blade: 4 to 8 cm, leaf color: green → autumn leaves → deciduous leaves, grass high: 50 to 130 cm , Flower diameter: 4 to 6 cm, flower season: July to September, flower color: yellow, flower shape: windmill type, number of pistols: 1, 5 cardiac skin, stamens number: 13 or more, fruit shape: conical shape.