This thorny shrub from southeast Europe is the most commonly cultivated member of the genus in North America. Although escapes have been widely reported across southern and coastal states, it does not appear to have become invasive north of the Gulf Coastal Plain (K, SE, W). From Ky. there is an old obscure report by Linney (1882) and a few recent colls. from cultivated plants (SERNEC 2024). P. crenulata (D. Don) M. Roem, from the Himalayas, is another commonly planted species. It was recently reported from TAYL (CW, EKY), and needs to be assessed for potential naturalization as well. Other species may be expected (W).