The Salicales or willow order of flowering plants, is comprised solely of the Salicaceae family. The Salicaceae family are trees and shrubs found predominantly in the Northern Hemisphere. Weeping willows refer to those species and hybrids of willow with a 'drooping habit', especially S. babylonica and its varieties from East Asia.
Poplar wood is also commercilly important as it is used for plywood, pulp and matches.
The soft, white wood of Populus is fabricated into plywood, pulpwood, excelsior, boxes, and matches. As with all other members of the salicales family, Populus catkins are male and female on different trees and their flowers contain no petals or sepals. Populus are generally insect pollinated but certain species are also wind-pollinated. Populus differ from Salix in that the leaves are roughly triangular in shape while Salix leaves are more often linear.