Populus alba L. is a species of poplar (or aspen) in the Salicaceae family, commonly known as white poplar, white poplar, silver poplar, poplar or aspen. It grows in relatively humid areas, sometimes in riparian forests, in regions with hot summers and mild to cold winters, and is native to the region that extends from the Iberian Peninsula and Morocco, to central Asia, and as far north as Germany and Poland.
P. alba is a medium-sized deciduous tree (mesophanerophyte), fast-growing, reaching heights of 16–27 m, rarely more, with a trunk that can reach 2 m in diameter. The crown is wide, and trees with multiple trunks or low branching are common. The bark is smooth and whitish, with characteristic diamond-shaped markings on young trees, which darken and fissure at the base on older trees. The shoots of the year, including the buds, are covered by a trichomatous layer that forms a fine whitish down.
The leaves are 4–15 cm long, five-lobed (5 unequal lobes), and initially covered by a thick, shiny whitish down on both sides, thicker on the underside, but the upper side loses this covering and becomes pale green when it reaches maturity, while the underside remains whitish until the leaves fall. In young, fast-growing trees, the leaves are larger and deeply lobed; in older trees and those where growth is slow for soil and climate reasons, the leaves are smaller and less indented.