Populus nigra is a commonly used scientific name for the European Black Poplar tree. Many people, especially gardeners and botanists, may need to use different synonyms for this species for various purposes. Some of the common synonyms for this tree species include the Eastern Cottonwood, the Italian Poplar, Black Poplar, Lombardy Poplar, and the Carolina Poplar. Other names used for the same species include Rio Grande Cottonwood, Populus italica, and Populus augustifolia. These synonyms are essential when looking for different varieties of the European Black Poplar tree or when referring to the same species in different parts of the world.