Often found near water, willow trees are extremely popular fast-growing trees in many areas of the country. They are low maintenance, growing up to 45 feet tall in perfect conditions. Willow trees are deciduous, regaining their leaves and blooms each year in spring. Although easy for which to care, there are a variety of diseases that can affect the leaves of willow trees. Read below for information on a few of the most common willow tree leaf diseases.
Willow scab is a fungus that attacks young leaves on a willow tree. It acts very quickly, producing olive green spore masses on the veins of the bottom of leaves in a very short period of time. When a willow tree is infected with willow scab, it often gets hit with black canker as well.
Black canker teams up with willow scab to create dark brown spots on the leaves of willow trees. Gray lesions with black borders appear on the stems of the leaves as well. The combination of black canker and willow scab is called willow blight. This tandem causes defoliation, significant death of parts of the willow, or even the death of the entire tree.
The gypsy moth is obviously not a disease in itself, but the moth caterpillars feed on willow tree leaves throughout the summer, often causing the leaves to drop. When this happens, the willow tree becomes weak and susceptible to other pests and a host of diseases.
Like gypsy moth caterpillars, willow leaf beetles attack willow tree leaves to create an environment in which the trees are susceptible to other pests and diseases. Willow leaf beetles feed on the leaves until defoliation occurs.
Crown gall is a bacterium that causes galls to form on leaf stems, resulting in stunted growth, discoloration and leaf death. Crown gall makes willow trees more likely to contract another disease.