Rhamnus cathartica
WARNING: LOCALLY INVASIVE SPECIES
Common Name: common buckthorn 
Type: Deciduous shrub
Family: Rhamnaceae
Native Range: Temperate Europe and Asia, northwestern Africa
Zone: 3 to 8
Height: 16.00 to 25.00 feet
Spread: 10.00 to 15.00 feet
Bloom Time: April to June
Bloom Description: Yellow-green
Sun: Full sun to part shade
Water: Medium
Maintenance: Medium
Suggested Use: Naturalize
Flower: Insignificant
Attracts: Birds
An invasive plant.

Culture

Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Prefers consistent moisture. Adapts to a variety of soils and environments. This species is considered to be shade-tolerant, fast-growing and somewhat short-lived. It has proved to be a troublesome self-seeder in many areas.

Noteworthy Characteristics

Rhamnus cathartica, commonly called common or European buckthorn, is a weedy, thicket-forming, deciduous shrub or small tree that typically grows to 16-25' tall. It is noted for having small spines at the branchlet ends. This buckthorn is native to Europe, western Asia and northern Africa. Plants were introduced to North America as ornamentals in the early 1800s, but have over time escaped landscapes and naturalized in open woods, wood margins, prairies, fields, pastures and roadsides in various locations primarily extending from Nova Scotia to Saskatchewan south to Missouri and Virginia. Elliptic to oval, mostly subopposite, hairless, dark green leaves (to 3" long) have 3-5 pairs of veins and toothed margins. Leaves retain green color long into fall, but eventually turn yellow. Plants are dioecious. Small yellow-green flowers bloom in spring (April-June). Fruit of the female tree is a round, fleshy, berry-like, black drupe (1/4" diameter) containing 3-4 seeds. Birds are very attracted to the fruit. Gray-brown bark, yellow inner bark and orange heartwood are distinctive.

Genus name comes from the Greek name of various spiny shrubs.

Specific epithet comes from the Greek word kathartikos meaning cleansing or purging in reference to use of the bark, leaves and fruit to prepare purgatives.

Problems

Common buckthorn is considered to be an invasive exotic species in many areas of eastern North America. It colonizes and spreads rapidly by self-seeding. Seeds typically fall to the ground around female plants, creating a dense understory of new seedlings the following year. Birds eat the drupes and distribute the seeds to more distant locations. Colonies of common buckthorn tend to out-compete and displace native plant populations, and they are very difficult to eradicate once established. In areas where oats are grown, this species is an alternate host of the crown rust of oats.

Garden Uses

Common buckthorn should no longer be planted in the landscape. It has been used in the past for a variety of ornamental purposes including hedge, privacy screen, windbreak and backdrop for perennial plantings.