Rhamnus rubra) is a species of flowering plant in the buckthorn family known by the common names red buckthorn and Sierra coffeeberry.

Frangula rubra is a spreading shrub approaching 2 metres (6+1⁄2 ft) in maximum height, its bark red or gray.

[1] The thin, deciduous leaves are generally oval in shape, green to grayish in color, and up to 6 centimetres (2+1⁄2 in) long.

The inflorescence is an umbel of up to 15 flowers with five pointed sepals opening into a starlike shape and five smaller, greenish petals.

It is native to the mountains and plateau areas of northern and eastern California and western Nevada,[citation needed] including the Sierra Nevada and Klamath Mountains, where it grows in many habitat types, including forests, chaparral, and sagebrush.