Characteristics of the genus:
- leaves are simple, alternate
- dioecious woody plants
- the flowers are in pendulous catkin-like inflorescences, developing before foliage
- the fruit is a capsule
- the seed is a fluffy achene
- poplars belong to fast-growing trees and to the group of soft deciduous trees (similar to willows)
From the point of view of systematics, poplars can be classified into five sections:
- section Leuce – white poplars and aspens (Populus alba, Populus tremula, Populus x canescens)
- section Aigeiros – black poplars (Populus nigra)
- section Tacamahaca – balsam poplars
- section Leucoides – large-leaved poplars
- section Turanga – shrub poplars
