cottonwood: see willow.

Any of several fast-growing North American trees of the genus Populus. Members of the willow family, cottonwoods have heart-shaped, toothed leaves and cottony seeds. The dangling leaves clatter in the wind. The eastern cottonwood (P. deltoides) has thick glossy leaves. Carolina poplar (P. angulata) and P. eugenei may be natural hybrids between P. deltoides and the Eurasian black poplar (P. nigra). The Alamo, or Fremont cottonwood (P. fremontii), is the tallest of the group. Seealso poplar.

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