There are at least nine members of the St. Johnswort and Waterwort order: Theales found in Montana. [1] Some of these species are exotics (not native to Montana). [2]
Family: Clusiaceae
Family: Elatinaceae
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 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.
Hypericum sphaerocarpum, the roundseed St. Johnswort or barrens St. John's wort, is a species of flowering plant in the St. John's wort family. It is native to the Eastern United States where it is primarily found in the Midwest and Mid-South as well as Ontario, Canada. Its preferred habitat is dry, calcareous glades and prairies.
Hypericum aegypticum is a species of flowering plant of the St. John's wort family (Hypericaceae) which is native to the Eastern Mediterranean. It was described by Carl Linnaeus in the second volume of his Species Plantarum in 1753, who named it after Egypt despite it not being distributed there. The plant is commonly known as shrubby St. John's wort or Egyptian St. John's wort in English. Like other members of section Adenotrias, it is found among limestone rocks in coastal areas. While it has been evaluated as threatened on the island of Malta, the species has no legal protections.
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.