Rhamnaceae

Defining Characteristics

• Shrubs or trees, occasionally climbing, with simple alternate (rarely opposite ) leaves
• Small, inconspicuous 4–5-merous flowers with petals often cucullate (hood-shaped) and wrapping around a single stamen
• Disk-like nectary (intrastaminal disk) prominent between petals and ovary
• Drupe , capsule , or schizocarp fruits
• Stipules often present; some genera have stipular spines
• Superior to half-inferior ovary

Notable Genera

• Rhamnus (buckthorn)
• Frangula (alder buckthorn)
• Ziziphus (jujube, lotus berry)
• Ceanothus (California lilac, redroot)
• Hovenia (Japanese raisin tree)
• Colletia (anchor plant)

Notes

Ziziphus jujuba (jujube) is cultivated for its edible fruits across Asia and the Middle East. Ceanothus species are important nitrogen-fixing shrubs in western North American chaparral. Common buckthorn (Rhamnus cathartica) is an aggressive invasive species in North America. Cascara sagrada (Frangula purshiana) bark has been used as a laxative.