Populus
Populus alba, Populus alba, Populus alba, Populus angustifolia, Populus balsamifera ssp. balsamifera, Populus balsamifera ssp. trichocarpa, Populus deltoides, Populus fremontii, Populus grandidentata, Populus nigra
Salix
Interactive Identification of New World Salix, Salix alaxensis, Salix amygdaloides, Salix Arboretum, Salix arbusculoides, Salix bebbiana, Salix exigua, Salix geyeriana, Salix glauca, Salix gooddingii
Description of Salicaceae
Habit and leaf form; Anatomy; Morphology; Physiology; Biochemistry; Geography.