COTTONWOOD

several fast-growing trees of North America, members of the genus Populus, in the family Salicaceae, with triangular, toothed leaves and cottony seeds. The dangling leaves clatter in the wind. Eastern cottonwood (P. deltoides), nearly 30 metres (100 feet) tall, has thick glossy leaves. Perhaps natural hybrids between this and Eurasian black poplar (P. nigra) are the Carolina poplar (P. angulata), and P. eugenei. Alamo, or Fremont cottonwood (P. fremontii), tallest of the group, is found in southwestern North America. Great Plains cottonwood (P. sargentii), of North America, has thick coarse-toothed leaves.