[Fr., from L. populus, a poplar.] A tall tree of thesame family as the willow, of rapid growth, and having soft wood, capable of many uses. About twenty species are known, growing chiefly in mild and cold climates. The most important are the gray poplar, a native of Britain ; the Lombardy poplar, of a conical form and without horizontal branches; the balsam poplar, the buds of which are covered with a sticky varnish called balsam ; the Canadian poplar, and the Cottonwood, a valuable timber tree, which is very abundant on the upper sections of the Mis- sissippi and the Missouri valleys.