Yellow-poplar (Liriodendron tulipifera) beautiful deciduous tree of our eastern forests. It is also called tulip poplar or tulip tree. Its common name is misleading because it is not in the Poplar (Populus) family but actually in the Magnolia (Magnoliaceae) family. It is thought the name “poplar” came from the way the leaves quivered in the wind much like true poplars. It commonly grows more than 100 feet tall and four to six feet in diameter. Yellow-poplar is an important timber and wildlife tree.