A tree 40 to 100 ft high, young branches clothed at first with a thick felt as in P. alba, much of which falls away by late summer; winter-buds slightly gummy, bright red-brown. Leaves heart-shaped, up to 7 or 8 in. long and nearly as wide, rounded at the apex, shallowly and rather evenly toothed, covered on both surfaces when they unfold with a thick whitish down, which soon falls away from the upper surface, leaving it dark green, but remains longer on the lower surface, especially on the midrib and veins. The leaves hang laxly on their stalks, which are round, felted at first like the shoot, 11⁄2 to 31⁄2 in. long. Male catkins 2 to 21⁄2 in. long; female catkins longer.
Native of the eastern United States; introduced in 1765. Until the introduction of several new Chinese species this poplar had the largest leaves of any in cultivation, but unfortunately it does not thrive well with us. Loudon observes that he had not seen plants more than 5 or 6 ft high, and no tree any bigger has been recorded.
For the section Leucoides, to which P. heterophylla belongs, see the introductory note to Populus.