Common Buckthorn

Fact SheetTreatmentRhamnus cathartica

Invader Images

    • Common/European buckthorn leaves are arranged sub-oppositely (almost alternate or opposite in some cases), oval, with toothed margins, and veins run parallel towards the tip
      Common/European buckthorn leaves are arranged sub-oppositely (almost alternate or opposite in some cases), oval, with toothed margins, and veins run parallel towards the tip
    • Characteristic orange inner bark on older growth
      Characteristic orange inner bark on older growth
    • Terminal "Thorns" on Common/European buckthorn
      Terminal "Thorns" on Common/European buckthorn

Common Look-alikes

    • Common chokecherry has droopy clusters of flowers and fruit, and leaf veins do not run parallel towards the tip like in Common buckthorn
      Common chokecherry has droopy clusters of flowers and fruit, and leaf veins do not run parallel towards the tip like in Common buckthorn

Identification

Appearance

Common buckthorn is a deciduous shrub or small tree that can grow to 25 ft. (7.6 m) in height. The bark is dark gray and the inner bark is orange (easily seen when the tree is cut). Twigs are usually tipped with a sharp spine.

Foliage

The leaf arrangement is usually subopposite, but examples of opposite and/or alternate arrangements are commonly found. Leaves are dark green, oval, 1.5 to 3 in. (3.8-7.6 cm) long, slightly serrate with 3 to 4 pairs of curving veins and a somewhat folded tip.

Flowers

Flowering occurs in the spring, when yellow-green, 4-petaled flowers develop in clusters of 2 to 6 near the base of the petioles. Plants are dioecious (male and female flowers occur on separate plants).

Fruits

Fruits are small, black berries that are 0.25 in. (0.6 cm) in diameter.

Check out the downloadable fact sheet above.

 

Biology

Ecological Threat

  • Birds and mammals feed on buckthorn berries during the winter, aiding in the dispersal of seeds. While buckthorn may benefit from this behavior, the feeding animals do not. Buckthorn berries contain emodin, a natural laxative, that prevents mammals from digesting sugars found in the berries.
  • Like many other invasive trees and shrubs, buckthorn leafs out early and retains its leaves into late fall, giving it a much longer advantageous growing season than native plants.
  • Buckthorn can increase the amount of nitrogen in the soil, impacting the composition of native species that can grow in the area.
  • Common buckthorn invades forests and can form dense thickets crowding out native shrubs and understory plants. Once established, it is difficult to remove.

Origin

Common buckthorn is a native of Europe and was introduced into the United States as an ornamental shrub

Habitat

Forests, forest edges, meadows, fields, disturbed areas

Life Cycle

Buckthorns reproduce by seed but plants can root sprout or regenerate even after they are cut or burned.  Plants mature at 5-6 years old. Seed production is prolific.  Common buckthorn fruits ripen from August to September while glossy buckthorn fruits ripen earlier—July to August. Seed germination rates are high and germinate well in the shade. Seeds remain viable for at least 2 years. Plants are usually dioecious; males do not produce fruit. Fruits are eaten by birds, mice, and deer. Seeds viable for 2-6 years.

Management Options

This species is Quarantined: Class B Noxious Weed

Check out the downloadable treatment sheet above.

Mechanical Control

Hand pull: Any time of year when the ground is soft, especially after a rain, hand pull small plants by the base of the stem. Be sure to pull up the entire root system. Hang from a branch to prevent re-rooting. For larger plants, use a wrenching tool. Continue to monitor the area every year for new seedlings.

Cut stump: Cut plants back any time of year. Wrap a few layers of burlap or thick plastic over the stump and tie tightly with twine. You will need to check stumps periodically and cut back any new growth.

Chemical Control

Cut stump: Cut the plant 4 inches above the ground. Use a drip bottle to apply an 18-21% glyphosate solution to the stump within one hour of cutting. This is best done in late summer through winter when plants are transporting resources to their root systems.

Low volume foliar spray:  This method is used for dense populations and best left to a contractor. In the fall, when native plants are losing their leaves, spray a 2% glyphosate or triclopyr solution on the entire leaf surface of the plant. In order to avoid drift to native plants, spray only on calm days.

  • Be careful not to damage or kill nearby native plants when conducting management work. And when using herbicides, always follow the instructions on the label.

How You Can Help

Native/non-invasive alternatives

Alder-leaved buckthorn (Rhamnus alnifolia), Cherries (Prunus sp.)

 

Native Perennials and Shrubs for Vermont Gardens

Choose native plants

Alternatives to Common Invasive Plants and Characteristics of Select Alternatives

 

Citations

Photo Credit

European Buckthorn, UGA1334006, Chris Evans, University of Illinois

European Buckthorn, 1334009, Chris Evans, University of Illinois

European Buckthorn, 5456140, Leslie J. Mehrhoff, University of Connecticut

Common Chokecherry, 0008188, Paul Wray, Iowa State University

Information Credit

Invasive.org, European buckthorn

Riverbank Media, European buckthorn

GoBotany, European buckthorn

Maine Natural Areas Program, Common buckthorn