The greatest impact of Common barberry is its potential to negatively affect the yield of cereal crops. The nonnative shrub acts as an alternate host for various rust species such as wheat rust, a fungal disease which can greatly reduce the yield of wheat, oat, and barley crops. As an alternate host, Common barberry can support the development of new genotypes of rust that are able to infect rust-resistant crops. Eradication of Common barberry has been associated with greater yields of grain crops.
Common barberry is native to Asia's mountains and has been introduced widely throughout Europe. Early New England settlers introduced the shrub to North America for its ornamental, food, and medicinal properties during the 1600s and the species has since escaped cultivation in many parts of the US. Wheat crop failure became associated with the presence of Common barberry, which led to the occurrence of many eradication attempts during the 1900s. Today the shrub is mainly a problem in the northeastern United States.
Common barberry can be distinguished from Japanese barberry by its serrated leaves, juicy berries, and three-pronged spines.
In the northeast, Common barberry invades abandoned fields, coastal grasslands, forest edges, roadsides, shrubby wetlands, and covered forests. The shrub typically begins producing fruit in its fourth to seventh year, but has been observed to produce fruit during its first year. The shrub produces yellow flowers in May or June and berries ripen by August or September. Seeds mature by October, persist on the shrub through the winter, and are mainly dispersed by birds and cattle.