Black cottonwood (Populus trichocarpa) is a large deciduous tree native to the Pacific Northwest coast. It is characterize by its fragrant, naked and sticky buds that become fragrant in the spring. Bark is old and deeply ridged, grey, with lots of young shoots. The leaves, deciduous themselves, are think and heart-shaped, five to fifteen centimeters long, with flat petioles. Leaves are sharp at the tip and have finely toothed margins. Flowers are found on catkins and separate plants (dioecious). The seeds it produces are white and fluffy, and thrives in moist and wet sites where it forms extensive stands.