- Author: Karey Windbiel-Rojas
If you are like me, you try to park your car under a tree in parking lots and on the street for some shade, especially with the hot weather we've had lately. Maybe you choose to park under a big hackberry tree, but when you return to your car, you notice droplets on your windshield and sticky stuff on the sidewalk, other cars, and the parking lot. What is this?
The sticky substance is called honeydew. The honeydew is excreted by a number of sap-sucking insects such as aphids, whiteflies, mealybugs, certain scale insects, and few others. On hackberry trees (widely planted in some cities), an insect called the woolly hackberry aphid produces a large amount of honeydew which drips from the leaves onto surfaces below.