Grow in consistently moist to wet soils in full sun to part shade. Tolerant of flooding and silting. Shallow, spreading root system is good for stabilizing soils and makes the tree an effective selection for erosion control. Soils should not be allowed to dry out. Prefers full sun. Avoid full shade. Prune as needed in late winter to early spring.
Salix nigra, commonly called black willow, is a medium to large, fast-growing, deciduous willow tree that typically grows to 30-60’ tall on single or multiple trunks topped by a spreading, rounded but sometimes irregular crown. It may soar to as much as 140’ tall in optimum growing conditions. It is native to moist to wet soils of floodplains, stream/river banks, swamps, marshes, sloughs, and ponds in the U. S. from Maine to Minnesota south to Colorado, Texas and Florida and in Canada from New Brunswick to Manitoba.
Bark of black willow is dark brown to black, developing deep grooves and a rough texture with shaggy scales as it ages. Narrow, lanceolate, finely toothed, medium to dark green leaves (to 6” long) taper to elongate tips. Variable fall color is usually an undistinguished greenish-yellow. Black willow is dioecious (male and female flowers appear on separate trees). Non-showy tiny yellowish-green flowers appear in catkins (both male and female catkins to 2” long) in early spring (late March-April) as the leaves emerge. Fruits are reddish-brown capsules. Wood is soft and weak.
Genus name is the Latin name for this plant.
Specific epithet from Latin means black in reference to the black tree bark.
Susceptible to blights, powdery mildew, leaf spots, crown gall and cankers. Trees may be visited by certain insect pests including tent caterpillars, willow sawfly, leaf beetles, aphids, and stem/twig borers. Wood is weak and tends to crack, with branches often damaged by ice and snow. Litter from leaves, twigs and branches may cause clean-up problems. Shallow roots may clog sewers or drains if trees are sited in improper locations.
Black willow is generally not recommended for use as a specimen in residential landscapes because of its susceptibility to breakage, potential insect/disease problems, need for soils that never dry out, litter problems, shallow spreading root system which may seek out water/sewer pipes, and mature size potential. In the right location, its shallow roots can act as a quality soil binder, providing excellent erosion control.