Hypericum perforatum, commonly known as St John's wort, is a flowering plant in the family Hypericaceae. It is a perennial plant that grows up to one meter tall, with many yellow flowers that have clearly visible black glands around their edges, long stamens, and three pistils. Probably a hybrid between the closely related H. attenuatum and H. maculatum that originated in Siberia, the species is now found worldwide. It is native to temperate regions across Eurasia and North Africa, and has been introduced to East Asia, Australia, New Zealand, and parts of North and South America. In many areas where it is not native, H. perforatum is considered a noxious weed. It densely covers open areas to the exclusion of native plants, and is poor grazing material. As such, methods for biocontrol have been introduced in an attempt to slow or reverse the spread of the species.
Hypericum is a genus of flowering plants in the family Hypericaceae. The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar regions. Many Hypericum species are regarded as invasive species and noxious weeds. All members of the genus may be referred to as St. John's wort, and some are known as goatweed. The white or pink flowered marsh St. John's worts of North America and eastern Asia are generally accepted as belonging to the separate genus TriadenumRaf.
Hypericum calycinum is a species of prostrate or low-growing shrub in the flowering plant family Hypericaceae. Widely cultivated for its large yellow flowers, its names as a garden plant include Rose-of-Sharon in Britain and Australia, and Aaron's beard, great St-John's wort, creeping St. John's wort and Jerusalem star. Grown in Mediterranean climates, widely spread in the Strandja Mountains along the Bulgarian and Turkish Black Sea coast.
Triadenum, known as marsh St. John's worts, is a small genus of flowering plants in the family Hypericaceae. The genus is characterized by opposite, blunt-tipped leaves and pink flowers with 9 stamens. They are distributed in North America and eastern Asia.
Geranium reuteri, the giant geranium, is a species of flowering plant in the family Geraniaceae, endemic to the Canary Islands. It was known for many years under the name Geranium canariense. In Spanish, it is called pata de gallo.
Hypericum hirsutum is a species of flowering plant in the family Hypericaceae, commonly known as hairy St John's-wort. It is found in Western Europe.
Hypericum ascyron, the great St. Johnswort or giant St. John's wort is a flowering plant in the family Hypericaceae.
Hypericum punctatum, the spotted St. John's wort, is a perennial herb native to North America. The yellow-flowered herb occurs throughout eastern North America into southern Canada. The process of microsporogenesis carried out by this plant is prone to errors in chromosomal segregation. It has a diploid number of 14 or 16. Insects are attracted to the plant's pollen and the hypericin in the plant's leaves is toxic to mammals.
Hypericum edisonianum, known as Arcadian St. John's wort, Edison's St. John's wort, and Edison ascyrum, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to Florida.
Hypericum tenuifolium, known as Atlantic St. John's-wort and sandhill St. John's-wort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is native to the Southeastern United States.
Hypericum japonicum, known as matted St. John's-wort, is an annual herbaceous flowering plant in the St. John's wort family Hypericaceae, in Hypericum sect. Trigynobrathys.
Hypericum tetrapetalum, the fourpetal St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is found in the Southeastern United States and Cuba. It was first described by Jean-Baptiste Lamarck in 1797.
Hypericum lancasteri, known as Lancaster's St. John's wort or as zhan e jin si tao in Chinese, is a species of flowering plant in the St. John's wort family Hypericaceae. The species has been awarded the Royal Horticultural Society's Award of Garden Merit.
Hypericum myrtifolium, the myrtleleaf St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to the Southeastern United States. It was first described by Jean-Baptiste Lamarck in 1797.
Hypericum oblongifolium, known as Pendant St. John's wort, is a species of flowering plant in Hypericumsect. Ascyreia.
Hypericum patulum, known as goldencup St. John's wort or yellow mosqueta, is a species of flowering plant in Hypericumsect. Ascyreia.
Hypericum virginicum, the marsh St. Johns-wort or Virginia marsh St. Johnswort, is a species of flowering plant in the family Hypericaceae. It is native to the central and eastern United States and eastern Canada.
Hypericum frondosum, the cedarglade St. Johnswort or golden St. John's wort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is native to the central and southeastern United States in dry, rocky habitats.
Hypericum aucheri, also known as Koramanotu in Turkish, is a herbaceous perennial flowering plant in the St. John's wort family Hypericaceae.
