Alien Plant Species (1 of 2) (IMAGE) Helmholtz Association Caption Originally, the Oregon holly grape (Mahonia aquifolium) is from the Pacific Northwest of United States of America. For their colorful flowers the evergreen shrub was quickly cultivated and spread by gardeners in Europe. Credit André Künzelmann/UFZ Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.