Berberis thunbergii, the Japanese barberry, Thunberg's barberry, or red barberry, is a species of flowering plant in the barberry family Berberidaceae, native to Japan and eastern Asia, though widely naturalized in China and North America, where it has become a problematic invasive in many places, leading to declines in species diversity, increased tick habitat, and soil changes. Growing to 1 m (3 ft 3 in) tall by 2.5 m (8 ft 2 in) broad, it is a small deciduous shrub with green leaves turning red in the autumn, brilliant red fruits in autumn and pale yellow flowers in spring..