Rhamnus is a genus of about 140 accepted species of shrubs or small trees, commonly known as buckthorns, in the family Rhamnaceae. Its species range from 1 to 10 m tall and are native mainly in east Asia and North America, but found throughout the temperate and subtropical Northern Hemisphere, and also more locally in the subtropical Southern Hemisphere in parts of Africa and South America. One species, the common buckthorn, is able to flourish as an invasive plant in parts of Canada and the U.S., where it has become naturalized.
Rhamnus (plant)
Rhamnus pumila, dwarf buckthorn
Rhamnus cathartica
The Rhamnaceae are a large family of flowering plants, mostly trees, shrubs, and some vines, commonly called the buckthorn family. Rhamnaceae is included in the order Rosales.
Rhamnaceae
Flowers of Ceanothus cuneatus
Bisexual flower of Helinus, with five sepals and petals, and a yellow, annular nectary disk. The small, clawed petals embrace the stamens.
Flowers of Ziziphus mucronata