A low-growing (2-3’ tall), dense, spiny shrub with small oval green leaves that turn reddish brown in fall. Plants have single sharp spines at each node and small, bright red, oblong berries.
Legal classification in Wisconsin: Proposed Restricted
Shade tolerant, drought resistant, and adaptable to a variety of open and wooded habitats, wetlands, old fields and disturbed areas.
It forms dense stands in natural habitats, dominating the forest understory by shading out native plants and changing foraging habits of wildlife.
Spreads vegetatively though horizontal branches that root freely when they touch ground.
Research shows infested forests have higher rates of Lyme disease carrying ticks.
White-tailed deer avoid browsing barberry due to the spines, preferring to feed on native plants, giving it a competitive advantage.
Prefers well drained soils and sunny habitats, but will survive and produce fruit in even heavily shaded environments.
Very invasive and widespread across Eastern United States and the Midwest.
Cultivars are widely planted as ornamentals.
Leaves & stems: Clustered in tight bunches above spines, the leaves are simple, alternate, small, and oval to spatulate shaped (wider at the tip than the base). Leaves may be green, bluish green, or dark reddish- purple depending on the cultivar. They leaf out in early spring. Plants have single sharp spines at each node. If a stem is cut, it will reveal that the inner bark is yellow. Branches root freely when they touch the ground.
Flowers: Flowers are cream-yellow colored, bowl-shaped with notched edges and 6 petals, and small (1/3” wide). They occur individually or in small clusters of 2-4, blooming in mid-spring.
Fruits & seeds: Small, bright red, oblong berries occur on narrow stalks both singly or in clusters. Berries persist on shrub into winter. Seeds are readily dispersed by birds.
Roots: Creeping, shallow roots are tough. Interior of roots are yellow. Branches root freely when they come into contact with ground.
Similar species: European barberry or common barberry (Berberis vulgaris) is also a non-native invasive (classified as Prohibited) but has spiny, toothed leaves and flowers in a long raceme.
Plants can be pulled out or dug up, easiest in early spring. Remove all roots and watch for resprouts. Cutting without herbicide will result in resprouting.
Mow or cut larger plants before seed set if not able to remove the entire plant.
Prescribed burns in early spring or late fall can be effective to kill seedlings. Use this method in fire-adapted communities to prevent mortality of surrounding desired vegetation.
Foliar spray with metsulfuron-methyl, triclopyr or glyphosate.
Adding a penetrating oil can be effective when used as a cut-stump treatment and basal barking.
Sources for content:
Czarapata, Elizabeth; Invasive Plants of the Upper Midwest: an illustrated guide to their identification and control. University of Wisconsin Press. 2005. Pg. 88-89
Center for Invasive Species and Ecosystem Health, Invasive.org. Japanese barberry