Populus, commonly called Poplars, Cottonwoods, and Aspens, are fast-growing and tough deciduous trees of great beauty. Many have great fall color, striking bark and statuesque growth habit. Spectacular assets in the garden, they can be a curse too. Most poplars will sucker. They are subject to pests and diseases. Their vigorous root system can heave pavement and clog drainage lines (avoid planting them near buildings). But to many gardeners, their remarkable beauty outweighs these issues.