Ask Mr. Smarty Plants

Salix matsudana, globe willow, is a native of eastern Asia. Willows generally are fairly weak, short-lived trees, susceptible to many insects and diseases, as well as dropping a lot of litter. The globe willow is often infected with slime flux, a bacterial disease that is soil-borne. They are frequently found in the Rocky Mountain area, in warm valleys, so while they are not native to North America, they are at least well adapted to the area in which you live.

This Colorado State University Extension The Globe Willow has excellent information on the care and problems facing this tree. Be sure and follow the links from the home page to see "Introduction," "Diseases and Insects," and "Aphids." In the last one, on aphids, follow the link to images of the giant willow aphid. If we saw something that big coming for us, we would probably drop some leaves, too. On that same webpage, there is some excellent advice: Always check with the Extension office in your county or state for specifics on pesticide selections and use. The website for your Davis County Extension office is apparently still under construction, but you can contact them at 28 E. South St., Farmington, UT 84025, phone 801-451-3412.