Berberis thunbergii

Origin: Japanese barberry is native to Japan and was introduced to the United States in the second half of the 19th century as an ornamental plant. It was used in hedgerows and erosion-control attempts and is still widely used in landscaping.

Description: Japanese barberry is a shrub 2-8 feet tall with clustered, untoothed, oblong to wedge-shaped leaves up to 1 inch in length. It develops pale yellow flowers in mid-spring or early summer which hang below thin, spiny branches in clusters of 2-5. Egg-shaped berries ripen to red in August and remain in place into winter.

Distribution: This invasive shrub is shade-tolerant and is found in a variety of habitats including canopy forests, open woodlands, fields, pastures, and wetlands.

Problem: Japanese barberry grows in dense stands, shading out and displacing native plants. It changes soil’s pH, nitrogen levels, and biological

activity. It is avoided by browsing white-tailed deer, furthering its competitive advantage, and its seeds are widely dispersed by birds.

Control: Hand-pulling of seedlings or small plants may be effective, but care should be taken not to disturb the soil more than necessary. Glyphosate (3%) or triclopyr (3%) may be sprayed onto leaves. This can be done anytime during the growing season. Well-established stands are probably best controlled by cutting stems to ground-level and spraying or painting the cut stumps with a 20% glyphosate solution or a 20% solution of triclopyr and basal oil.

USE PESTICIDES WISELY: Always read the entire pesticide label carefully, follow all mixing and application instructions and wear all recommended personal protective gear and clothing. Contact your state department of agriculture for any additional pesticide use requirements, restrictions or recommendations.