Black Cottonwood, Balsam Poplar: Populus trichocarpa (Synonyms: Populus balsamifera, Populus balsamifera var. californica, Populus balsamifera ssp. trichocarpa) -
Quaking Aspen: Populus tremuloides (Synonyms: Populus tremula ssp. tremuloides, Populus tremuloides var. vancouveriana) -