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bark=smooth white, black marks;  buds and twigs have white powdered, easily rubbed off
white poplar Populus alba

tree=very tall thin, many small branches
European black poplar Populus nigra

tree=small, bark=light gray (darker at base);  forming colonies;  buds=shiny, against twig
quaking aspen Populus tremuloides
tree=small, bark=light gray (darker at base);  forming colonies;  buds=dusty gray away from twig
big-toothed aspen Populus grandidentata

Learn more about poplar/aspen genus Populus (Populus spp.)

Uses by native peoples
(Ethnobotany database) Used as host by caterpillars of 367 species
of 🦋 butterflies and moths, in some areas.
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