Ask Mr. Smarty Plants

If it's not No. 1, "What's wrong with my weeping willow?" is right up there close to the top of most frequently asked questions to Mr. Smarty Plants. On today's slate, alone, there are three questions. If you search on "weeping willow" in the Ask Mr. Smarty Plants section, you get ten possibilities. The problem is, the question is the wrong question asked at the wrong time. We wish that gardeners would ask "Should I plant a weeping willow?" BEFORE they purchase and plant it. Non-native to the United States, Salix x sepulcralis is a hybrid of a Chinese species (Peking willow) and a European species (white willow), and is said to grow in Zones 5 to 8 in the United States. It is weak-wooded, fast-growing and, therefore, short-lived. It has aggressive roots, can lift sidewalks and interfere with sewer lines, often growing on soil surface, making a problem with mowing. It is susceptible to a number of pests and diseases, and notorious for littering the ground beneath it. See this University of Florida Extension website on Weeping Willows for more information. Also, in case you think we're exaggerating, see this Q&A from North Dakota State University Extension on weeping willows.

Both of the referenced websites will give you a number of things that could be wrong with your willow. The only site we found that specifically mentioned dry, brown leaves on willows is this one from the Government of Canada Forest Invasive Alien Species Willow Scab. The scabs, recognizable by the browned or blackened foliage they cause in infected trees, are fungus diseases. In the case of willow scab, a fungus is the cause. The fungus initially attacks the leaves from the twig up, turning it blackish or brown, and the leaf dies. It can be followed by canker and, ultimately, the death of the tree. On the spot examination by a competent arborist is probably the only way to know what is really causing the problem and what to do about it. You might also contact the Penn State Cooperative Extension Service for Indiana County.