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

Description

''Frangula rubra'' is a spreading

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

approaching in maximum height, its bark red or gray. The thin,

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

leaves are generally oval in shape, green to grayish in color, and up to long. The edges are smooth or faintly toothed. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is an

umbel UMBEL (Upper Mapping and Binding Exchange Layer) is a logically organized knowledge graph of 34,000 concepts and entity types that can be used in information science for relating information from disparate sources to one another. It was retired ...

of up to 15 flowers with five pointed

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s opening into a starlike shape and five smaller, greenish petals. The fruit is a

drupe In botany, a drupe (or stone fruit) is a type of fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pip'' (UK), ''pit'' (US), ''stone'', or ''pyrena'') of hardened endocarp with a seed ...

which ripens to black. It measures just over 1 cm long and contains 2 seeds.

Distribution and habitat

It is native to the mountains and plateau areas of northern and eastern

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and western

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

, including the

Sierra Nevada The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

and

Klamath Mountains The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast R ...

, where it grows in many habitat types, including forests,

chaparral Chaparral ( ) is a shrubland plant plant community, community found primarily in California, southern Oregon, and northern Baja California. It is shaped by a Mediterranean climate (mild wet winters and hot dry summers) and infrequent, high-intens ...

, and sagebrush.

Adverse effects

The berry is inedible and may have a laxative effect.

References

External links

Jepson Manual Treatment - ''Rhamnus rubra''USDA Plants Profile: Frangula rubra''Rhamnus rubra'' - Photo gallery
rubra Flora of California Flora of Nevada Flora of Oregon Natural history of the California chaparral and woodlands Flora of the Cascade Range Flora of the Great Basin Flora of the Klamath Mountains Flora of the Sierra Nevada (United States) Taxa named by Edward Lee Greene Plants described in 1887 Flora without expected TNC conservation status {{Rhamnaceae-stub