Cottonwood is a domestic hardwood
Cottonwood includes several species of the genus Populus. Most important are eastern cottonwood (P. deltoides and varieties), also known as Carolina poplar and whitewood; swamp cottonwood (P. heterophylla), also known as cottonwood, river cottonwood, and swamp poplar; black cottonwood (P. trichocarpa); and balsam poplar (P. balsamifera). Eastern and swamp cottonwood grow throughout the eastern half of the United States. Greatest production of lumber is in the Southern and Central States. Black cottonwood grows on the West Coast and in western Montana, northern Idaho, and western Nevada. Balsam poplar grows from Alaska across Canada and in the northern Great Lakes States.
The heartwood of cottonwood is grayish white to light brown. The sapwood is whitish and merges gradually with the heartwood. The wood is comparatively uniform in texture and generally straight grained. It is odorless when well dried. Eastern cottonwood is moderately low in bending and compressive strength, moderately stiff, moderately soft, and moderately low in ability to resist shock. Most strength properties of black cottonwood are slightly lower than those of eastern cottonwood. Both eastern and black cottonwood have moderately high shrinkage. Some cottonwood is difficult to work with tools because of its fuzzy surface, which is mainly the result of tension wood.
Cottonwood is used principally for lumber, veneer, pulpwood, excelsior, and fuel. Lumber and veneer are used primarily for boxes, crates, baskets, and pallets.
*Much of the base wood information presented here is made available by the USDA FPL FS. If you are interested in a much more technical description of wood properties, I encourage you to visit the source.