Leaves are alternate, simple, long and thin.
The black willow is the largest of the willows found in Iowa, attaining a height of 75 feet and a diameter of 2 feet or more. It has an irregular, open crown and frequently a cluster of main trunks. They are shiny light green above, duller below and often velvety along the midrib. There are prominentleaf-like stipules at the base of the leaf stem. The buds are reddishbrown.