Salix nigra, commonly called black willow, is a medium-to-large, fast-growing, deciduous willow tree. It typically grows to 70-80’ tall on single or multiple curved trunks, typically 1-2' thick, 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. It is the largest of NC's willow species and grows nearly everywhere in the state, save for the high peaks of the Mountain region.
The black willow grows in consistently moist to wet soils in full sun to part shade. It is tolerant of many soil types so long as ample moisture is present. It is tolerant of flooding and silting. It has a shallow, spreading root system that is good for stabilizing soils and makes the tree an effective selection for erosion control. Soils should not be allowed to dry out. It prefers full sun. Avoid full shade.
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. This is a perfect tree near a pond or to stablize banks of a stream.
While it bares similarity to the also native Coastal Plains Willow, the two species can be told apart by the leaves– S. nigra has thinner leaves and lacks S. caroliniana's whitish undersides.
This is a larval host plant for several butterflies. Eastern Tiger Swallowtail (Papilio glaucus), Mourning Cloak (Nymphalis antiopa) , Red-spotted Purple (Limenitis arthemis astyanax), Viceroy (Limenitis archippus), and Eastern Comma (Polygonia comma). Its buds and catkins are eaten by birds. It provides excellent leaf season cover for birds in wetland sites. Salix genus supports numerous specialized bees.