|Species:||R. californica—F. californica|
Rhamnus californica, now reclassified as Frangula californica,    and commonly known as California coffeeberry, coffeeberry, and California buckthorn, is a species of flowering plant in the family Rhamnaceae, the buckthorns.
Rhamnus californica is a shrub 3–12 feet (0.91–3.66 m) tall. It is variable in form across subspecies. In favorable conditions the plant can develop into a small tree over 12 feet (3.7 m) tall.More commonly it is a shrub between 3–6 feet (0.91–1.83 m) tall.
The branches may have a reddish tinge and the new twigs are often red in color. The alternately arranged evergreen leaves are dark green above and paler on the undersides. The leaves have thin blades in moist habitat, and smaller, thicker blades in dry areas.
Inflorescence and fruit
The 1/8" greenish flowers occur in clusters in the leaf axils, have 5 sepals, and 5 shorter petals.
It blooms in May and June.
- Frangula californica subsp. californica — California coffeeberry; widespread in western California. Fruit with two seeds; twigs red; leaves with conspicuous veins. 
- Frangula californica subsp. crassifolia — serpentine hoary coffeeberry; endemic to the Inner North California Coast Ranges, on serpentine soils.
- Frangula californica subsp. cuspidata — Sierra hoary coffeeberry; Southern Sierras, Transverse Ranges, Peninsular Ranges. 
- Frangula californica subsp. occidentalis — Western california coffeeberry; on serpentine soils in northern California and southwestern Oregon, in the Klamath Mountains and North California Coast Ranges. Fruit with three seeds; twigs brown; leaves with inconspicuous veins.  
- Frangula californica subsp. tomentella — hoary coffeeberry.  
- Frangula californica subsp. ursina — desert hoary coffeeberry; endemic to the San Bernardino Mountains and Mojave Desert sky islands.
This shrub is a member of many plant communities and grows in many types of habitat, including California chaparral and woodlands, coastal sage scrub, and California oak woodlands. It grows in forest types such as foggy coastal oak woodlands, Coast redwood forests, California mixed evergreen forests, and mountain coniferous forests. 
It can be found alongside chaparral whitethorn (Ceanothus leucodermis), toyon (Heteromeles arbutifolia), skunkbush (Rhus trilobata), redberry (Rhamnus crocea), and western poison oak (Toxicodendron diversilobum). In brushy mountain habitat it grows among many species of manzanita.
The plant reproduces sexually by seed and vegetatively by sprouting. After wildfire or cutting, the plant generally resprouts from its root crown. Reproduction via seed is most common in mature stands of the plant. It produces seeds by 2 or 3 years of age. Seeds are mature in the fall. Seed dispersal is often performed by birds, which are attracted to the fruit; some plants are so stripped of fruit by birds that hardly any seeds fall below the parent plant.
This long-lived plant is persistent and becomes a dominant species in many habitat types, such as coastal woodlands. In the absence of wildfire, the shrub can grow large, with a wide spread that can shade out other flora. When fire occurs, the plant can be very damaged but it readily resprouts from the surviving root crown, which is covered in buds for the purpose. It reaches its pre-burn size relatively quickly.
This plant is cultivated as an ornamental plant by plant nurseries, for planting in native plant, water conserving, and wildlife gardens; in large pots and containers; and in natural landscaping and habitat restoration projects.    
- Frangula (Rhamnus) californica 'Eve Case' — Eve Case coffeeberry; smaller and more compact (3-6' H x 3-4' W), with denser foliage and larger berries than species.  Introduced by the Saratoga Horticultural Foundation in 1957.
- Frangula (Rhamnus) californica 'Leatherleaf' — Leatherleaf coffeeberry; with black-green foliage. 
- Frangula (Rhamnus) californica 'Mound San Bruno' — smaller leaves, more dense and compact, particularly tolerant of garden conditions. 
- Frangula (Rhamnus) californica ‘Seaview’ — a ground cover variety. 
Food and medicine
Native Americans of the west coast of North America had several uses for the plant as food, and used parts of it as a traditional medicinal plant. Several tribes of the indigenous peoples of California ate the fruit fresh or dried.
The Ohlone people used the leaves to treat poison oak dermatitis.  The Kumeyaay people had similar uses for its bark.  The Kawaiisu used the fruit to treat wounds such as burns.  The bark was widely used as a laxative by the indigenous peoples. 
- Jepson (TJM2): Frangula californica . accessed 4.5.2015
- NPGS/GRIN: Frangula californica information . accessed 4.4.2015
- USDA: Frangula californica . accessed 4.5.2015
- Frangula californica. NatureServe. 2012.
- Flowering Plants of the Santa Monica Mountains, revised 2000, p. 168
- McMurray, N. E. 1990. Rhamnus californica. In: Fire Effects Information System. USDA FS. Rocky Mountain Research Station, Fire Sciences Laboratory.
- Calflora: Frangula californica − Subspecies and Varieties
- Calflora: Frangula californica subsp. californica . accessed 4.5.2015.
- Jepson: Frangula californica subsp. californica . accessed 4.4.2015.
- Jepson: Frangula californica subsp. crassifolia . accessed 4.4.2015.
- Calflora: Frangula californica subsp. cuspidata . accessed 4.5.2015.
- Calflora: Frangula californica subsp. occidentalis . accessed 4.5.2015.
- Jepson: Frangula californica subsp. occidentalis . accessed 4.4.2015.
- Calflora: Frangula californica subsp. tomentella . accessed 4.5.2015.
- Jepson: Frangula californica subsp. tomentella . accessed 4.4.2015.
- Jepson: Frangula californica subsp. ursina . accessed 4.4.2015.
- NPIN—Lady Bird Johnson Wildflower Center: Frangula californica (California buckthorn, California Coffeeberry)
- Las Pilitas Horticulture Database: Frangula (Rhamnus) californica (Coffeeberry)
- California Native Plant Society, "Gardening with Natives" blog: Frangula californica (California Coffeeberry); posted September 28, 2010; accessed 4.4.2015
- Native Plants Network.org: Propagation protocol for production of container Frangula californica
- Theodore Payne Foundation: Frangula (Rhamnus) californica
- California Native Plants for the Garden. Bornstein, Carol, David Fross, and Bart O'Brien. Los Olivos, CA: Cachuma Press. 2005.
- Theodore Payne Foundation — California Natives Wiki: Frangula (Rhamnus) californica 'Eve Case'
- San Marcos Growers horticulture database: Frangula (Rhamnus) californica 'Eve Case'
- San Marcos Growers horticulture database: Frangula (Rhamnus) californica 'Leatherleaf'
- San Marcos Growers horticulture database: Frangula (Rhamnus) californica 'Mound San Bruno'
- University of Michigan, Dearborn − Native American Ethnobotany: Frangula californica . accessed 4.4.2015
- Chesnut, V. K. (1902). Plants used by the Indians of Mendocino County, California. Government Printing Office. p. 407. Retrieved 24 August 2012.
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