The seeds are borne on cottony structures that allow them to be blown long distances in the air before settling to ground.

Eastern cottonwood (Populus deltoides) is one of the largest North American hardwood trees, although the wood is rather soft.

In the typical subspecies P. d. deltoides (Vermont south to northern Florida and west to about Michigan), the leaves are broad and triangular, 7–15 cm across at the base.

Further west (Minnesota south to eastern Texas), the subspecies P. d. monilifera (plains cottonwood; syn.

[3] In the United States, the species can be found in Arizona, California, Colorado, Idaho, Nevada, New Mexico, Texas, and Utah.

[6][7] Black poplar (P. nigra) is native to Europe and Western Asia, is distinct in its much smaller leaves, 5–11 cm (2.0–4.3 in) across, with a more rhombic (diamond) shape.

Cottonwoods are widely grown for timber production along wet river banks, where their exceptional growth rate provides a large crop of wood within just 10–30 years.