Synonyms: Berberis thunbergii var. atropurpurea

Common Names: Barberry, Thunberg's barberry, Japanese berberis

Description: Barberry is a common horticultural species and frequently escapes from cultivation; deer herbivory minimal. The non-native common barberry (B. vulgaris) is also invasive but was eradicated from large parts of its range in the early twentieth century as it is a host to black stem grain rust.

Habit: Spiny, deciduous shrub; typically 0.5-1 m (2-3 ft) tall.

Leaves: Simple, alternate, oval to spoon shaped with smooth margins, 1.3-2 cm (0.5-0.75 in) long; bright green above, lighter below, in clusters at each node, red to purple in the fall depending on the cultivar.

Stems: Numerous; spiny; slightly curving; older stems gray; twigs and young stems turning reddish brown in winter; inner bark yellow.

Flowers: Small, yellow in color, 6 petals, stalked, single or in small clusters of 2-4 blossoms; blooms April through May.

Fruit and seeds: Small, bright red, egg-shaped berries found singly or in clusters on slender stalks; mature in midsummer; remain on stems into winter; often dispersed by birds, deer, turkey and grouse. Some cultivars appear to produce little or no fruit.

Habitat: Found along woodland edges, open woods, roadsides, stream banks, old fields; tolerates a range of soil, moisture and light conditions; can establish under forest canopy.

Reproduction: By seed, creeping roots and cut stumps; branches root freely where they touch the ground.

Similar species: American barberry (B. canadensis) has toothed leaves and usually three pronged spines.

Monitoring and rapid response: Monitor sunny open sites and edges in spring when barberry leafs out before native shrubs. Begin control efforts in highest quality areas; hand pull or dig young plants, removing all roots. Target mature shrubs that provide a source of seed; cutting effective when cut stumps are treated with herbicide; foliar herbicide treatment is effective in areas with few native plants. In fire-adapted communities, late spring burns with good fuel may kill seedlings.

Credits: The Michigan Natural Features Inventory (MNFI) has partnered with MISIN to provide the information in this fact sheet. Species images and/or information were used with permission from "A Field Identification Guide to Invasive Plants in Michigan's Natural Communities" and "A Field Guide to Invasive Plants of Aquatic and Wetland Habitats for Michigan.

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