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 maculatum, commonly known as imperforate St John's-wort, or spotted St. Johnswort, is a species of perennial herbaceous flowering plant in the family Hypericaceae. It is native to Europe and Western Asia where it grows in moist meadows.
Trillium recurvatum, the prairie trillium, toadshade, or bloody butcher, is a species of perennial herbaceous flowering plant in the family Melanthiaceae. It is native to parts of central and eastern United States, where it is found from Iowa south to Texas and east to North Carolina and Pennsylvania. It grows in mesic forests and savannas, often in calcareous soils. It is also known as bloody noses, red trillium, prairie wake-robin, purple trillium, and reflexed trillium, in reference to its reflexed sepals.
Hypericum pulchrum is a flowering plant in the family Hypericaceae, commonly known as slender St John's-wort. It is native to Western Europe.
Triadenum fraseri, commonly known as bog St. John's wort, Fraser's St. John's wort, and Fraser's marsh St. John's wort, is a perennial flowering plant in the family Hypericaceae that grows in wetlands of Canada and the northern United States. It is named after John Fraser (1750–1811), a Scottish botanist and widely travelled plant collector.
Hypericum buckleyi, known as Blue Ride St. John's wort and Buckley's St. Johnswort, is a rare species of flowering plant in the family Hypericaceae found only in the Appalachian Mountains of the southeastern United States. The species is listed in the state of Georgia (S1), South Carolina (SX), and North Carolina (S3).
Gerould S. Wilhelm is an American botanist and lichenologist. He is known as author of several floras of the Chicago Region and the development of the Floristic Quality Assessment methodology, a tool to assess the integrity of natural areas. He is the director of research at Conservation Research Institute, a nonprofit organization "dedicated to the promotion of planning, design, restoration, and long-term management of sustainable ecological systems in built and natural environments through applied research, education, and outreach."
Hypericum swinkianum, known as Swink's St. John's wort, is a shrub in the St. John's wort family. It was named after Chicago Region botanist Floyd Swink (1921-2000).
Dr. Floyd Allen Swink (1921-2000) was an American botanist, teacher of natural history, and author of several floras of the Chicago region.
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.
Laura Rericha-Anchor is an American biologist with expertise in botany, ornithology, entomology, and ecology of the Midwestern United States.
Hypericum canadense, known as Canadian St. Johns-wort, lesser St. John's wort, and lesser Canadian St. Johnswort, is a flowering plant in the genus Hypericum. It is a yellow-flowering annual or perennial herb native to North America and introduced to Ireland and The Netherlands. The specific epithet canadense means "Canadian".
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 galioides, the bedstraw St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to the Southeastern United States.
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 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 assamicum is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to India. Hypericum assamicum is one of two species of Hypericum in the section Hypericum sect. Sampsonia.
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 lobocarpum, commonly called fivelobe St. Johnswort, is a species of flowering plant in the St. Johnswort family (Hypericaceae). It is native eastern to North America, where it is found primarily in the western portion of the southeastern United States. Its typical natural habitat is in open wet areas, such as stream banks, lake margins, swamps, and pine savannas.
Hypericum coris, the heath-leaved St. John's wort, also called yellow coris, is a species of flowering plant in the family Hypericaceae, and is the type species of sect. Coridium. It is a low shrub, and it is found in Switzerland and northwestern Italy. The species has been a popular garden plant since the 18th century, valued for its long flowering period and for how well it adapts to cultivation.
