Japanese barberry (Berberis thunbergii) is a compact, spiny, deciduous shrub native to Japan that was introduced to North America in the 1800's as an ornamental plant. While it invades a variety of habitats from forested communities to open fields and wetlands, it is most problematic in mature forests in the eastern United States where it forms dense thickets, outcompeting native shrubs and herbaceous species. It has spread throughout many eastern and midwestern states.
Japanese barberry is a deciduous shrub, usually 3- to 6-feet tall. Leaves are simple, smooth-edged, oval, and alternately arranged in tight clusters along the erect or arching stems. Its small yellow flowers bloom in May, singly or in small clusters, turning into bright red oblong fruits in mid-summer. Japanese barberry is mostly multi-stemmed with additional stems arising from rhizomes. It is highly invasive due to high seed production, good seed viability, sexual reproduction, vegetative reproduction, shade tolerance, and seed dispersal by birds and other animals. In North Carolina, it has been observed in the Mountains and Piedmont.
Fact Sheet: Japanese Barberry