Hypericum gramineum, commonly known as small St. John's wort or grassy St. Johnswort, is species of flowering plant in the St. Johns wort family Hypericaceae. It is found in parts of Southeast Asia, Oceania, and the Pacific. Description Grassy St. Johnswort is a small annual or perennial herb with a height of . Its flowers are 5–12 mm in diameter. The plant causes photosensitization and enteritis. Distribution and habitat Hypericum gramineum occurs in New Zealand, Australia, New Caledonia, Papua-New Guinea, Vietnam, Taiwan, China (Hainan, Yunnan), India (Meghalaya, Manipur), Bhutan, and the United States (Hawaii). It is found in every state and territory of Australia. It grows in open grassy and shrubby habitats. Reference list gramineum Flora of China Flora of East Himalaya Flora of Assam (region) Flora of Vietnam Flora of Australia Flora of New Caledonia Flora of New Zealand Flora of New Guinea