Willows are deciduous shrubs or trees with invasive roots, according to the University of California. The most common shrub willow is the weeping willow (Salix alba Tristis). The weeping willow has a distinctive look with its long graceful branches that sweep down to the ground to form a cascading canopy. This shrub, which is often used in landscaping, resembles the golden willow with its similar leaves and twig color, although its branches are exceptionally thin and pendulous, notes North Dakota State University.
The weeping willow has alternate, yellow-green leaves that are 3 to 6 inches long, according to Virginia Tech. Weeping willow flowers are fuzzy and resemble erect catkins. The shrub's fruit is light brown and contains numerous cottony seeds that ripen from late May to early June. The weeping willow's grayish bark is sporadically wrinkled.
Weeping willows originally came from China, according to Brandeis University. They're now commonly found across North American, from as far north as Ontario to as far south as Georgia and as far west as Missouri. They are often found growing in exceptionally moist soils near bodies of water.
Root rot sometimes infects root systems, which causes the plant to decline. Crown gall is a disease in which galls form on the plant. Remove infected plants and don't replant in the same spot for two years, warns the University of Florida Extension. Willow scab is a fungal disease that starts in twigs, causing cankers and killing young shoots. Signs of the problem are olive-green spore masses found on veins of the undersides of leaves. Powdery mildew produces a white coating on leaves, but isn't serious.
Considerations and Warning
Plant weeping willows in full sun or partial shade, recommends the National Center for Conservation Science and Policy. These plants are drought-tolerant and can grow in either acidic or alkaline soil. Soil should be well-drained, but moist. They can also grow in loamy or clay soils. Because of the tree's extremely brittle branches, they can easily break, which makes cleaning up the litter a continual job, reports North Dakota State University.
Besides having a dramatic appearance, the weeping willow also has a dramatic history, explains the National Center for Conservation Science and Policy. Cuttings from the tree were carried on trade routes from China. Because the shrub occurred along the Euphrates River, the famous botanist, Linnaeus, gave the plant a biblical scientific name of "babylonica." A weeping willow tree later became a refuge for Napoleon as he sat under the shade of the tree while exiled on the Island of St. Helena. After the famous French emperor was buried under a weeping willow, cuttings from Napoleon's favorite tree became valuable treasures for his admirers around the world.