The black willow (Salix nigra) is the largest willow species in the New World, according to the National Audubon Society Field Guide to Trees. The black willow is a common tree along waterways and wetlands in the eastern half of the United States. As such, the black willow is important in preventing erosion and the tree can tolerate flooded ground for long periods. Black willow can be a valuable landscaping tree if you have an area of property that is constantly wet in which to plant it.
Black willow averages about 50 to 65 feet in height, but specimens as tall as 138 feet exist, reports the United States Department of Agriculture Forest Service site. The black willow will often develops multiple stems and the tree generally branches off at the trunk. The trunk sometimes contorts as the tree develops and the black willow often leans. The lance-shaped leaves grow to 6 inches long and have a slightly curved look. The thin, gray bark is smooth and the yellow flowers, called catkins, hang down and are 1 1/2 inches long. They develop into an orange capsule full of seeds by summer.
The geographic range of the species extends from southern sections of New Brunswick in Canada south to northern Florida. The black willow grows native from the Deep South into southern Texas and from there northward to Minnesota. The tree also grows now in many of the Western states after its introduction as a means to control erosion.
Starting a black willow tree can be as simple as breaking a branch off one and placing it into moist soil near water. The tree can grow in partial shade if necessary but will flourish in full sun. Soil that stays wet year-round is best for this type of tree and even floods will not deter it from growing. The black willow can mature in as little as 30 years, but is not a long-lived species. You can quickly establish black willow in a wet spot, but need to be careful the tree, which produces a myriad of seeds, does not form an impenetrable thicket in the area.
The roots of the black willow, while shallow, are far-reaching and work to hold soil together. The tree has benefit as a source of food for wildlife. The birds around your home will nest in it and eat its catkins and seeds, while deer will snack on the twigs and the leaves. Animals such as beavers and rabbits enjoy the bark and the buds on the branches.
The black willow is a close relative of the weeping willow, an ornamental native to the Orient. Black willow wood was used to make artificial limbs for people before the advent of plastics. Crates, boxes, charcoal and wooden ware are also products made from the wood. Black willow is so tolerant of water that one tree in Illinois lived despite being totally underwater for at least 32 days.