Tree Profiles: Weeping Willow (Salix babylonica), Part 1
This is the first half of a two part series on weeping willow. The following examines the tree’s distribution and habitat, developmental traits, longevity, height, bark, leaves, flowers, fruit, and root system, as well as how it can be propagated.
Weeping willow (Salix babylonica), also called Babylon willow, is a species of willow native to northern China. Historically, weeping willow was used as a popular trading item along the Silk Road. It was introduced to England from Syria in 1730. It was first described and assigned its scientific name by the Swedish botanist and plant pathologist, Carl Linnaeus, in 1736. Linnaeus named weeping willow salix babylonica after mistaking it for the trees described growing along the rivers of Babylon in the Bible. The trees mentioned in the Bible were likely poplars, which are members of the willow family (Salicaceae). The species that Linnaeus observed was the variety that had been introduced into the Clifford Garden in Hartekamp in the Netherlands.
Distribution & Habitat
Weeping Willow is native to northern China, but has become widespread across North America, Europe, and Asia.
Weeping willow is a medium to large sized deciduous tree. It grows rapidly, adding over 2 feet of height per year. Weeping willows prefers full sun or partial shade. To thrive, weeping willow requires at least four hours of direct sunlight each day. Weeping willow has a rounded growth habit. Its branches are brittle, and tend to crack under moderate to heavy snow or ice accumulation. They may also suffer breakages due to heavy winds. As such, weeping willows should be routinely pruned each year to limit environmental damage. The most ideal period to prune weeping willow is from late winter to early spring. In fall, weeping willows tend to produce an abundance of leaf and twig litter.
Weeping willow has a short lifespan. On average, weeping willows live 20 to 30 years. Weeping willows growing in optimal conditions may live for up to 75 years.
Weeping willow generally reaches heights of 30 to 40 feet, with a 35 to 40 foot spread. Outliers may grow 60 to 80 feet.
The bark of weeping willow is gray and deeply furrowed. It has a rough texture.
Weeping willow has yellowish-brown shoots, with small buds. When the leaves initially expand, they are light green, with a grayish-green underside. In autumn, the leaves turn golden-yellow. The leaves are alternate, with a spiral arrangement. They have serrated margins, and long tips. They can grow 4 to 16 cm long, and 0.5 to 2 cm wide.
Weeping willow flowers form in catkins from April to May. The catkins are dioecious, with the males and females developing on willows of the same gender. The catkins are green, with a silver tinge.
Weeping willow produces brown fruit that can reach up to ¼ inches in diameter.
Weeping willow can be easily propagated from stem cuttings. The stem cuttings must be at least two feet long. Stem cuttings can be removed from mature willows in winter, when the trees are dormant. Perform the cut directly at the base. Place the cutting into the soil in late winter or early spring. Ensure that the soil the willow has been planted in remains moist throughout the growing season.
Weeping willow establishes a shallow root system. When planted in residential settings, weeping willow roots can become invasive, growing through the cracks of sewage drains, and into underground pipes. The roots should be fed a balanced fertilizer each year to support their growth, and promote the formation of healthy stems and flowers. Fertilizer should contain an equal ratio of nitrogen, phosphorous, and potassium.
Photo courtesy of Leonora Enking CC-by-2.0