Tian Ji Huang

Hypericum japonicum, sometimes called Japanese St John's wort or matted St John's wort, is a small slender annual to short-lived perennial herb of the Hypericaceae family, typically only 5 to 35 cm tall. Stems are erect or ascending, four-angled, often branched from the base, and root at the lower nodes when prostrate. Leaves are opposite, sessile, ovate to broadly elliptic, 4 to 15 mm long, with three to five longitudinal veins from the base and translucent glandular dots visible against light; black marginal glands are absent. Small bright yellow five-petaled flowers, 5 to 8 mm across, are borne singly or in few-flowered terminal cymes; the numerous stamens are not arranged in distinct fascicles. The fruit is a small ovoid capsule. It grows in damp open ground, ditches, and rice-field margins throughout East and Southeast Asia.