Are you seeing cars, sidewalks, driveways, or other plants covered in sticky stuff, especially those under trees? This sticky substance, called honeydew, is produced by certain insects that excrete it when they feed on plants. Plant leaves look shiny and honeydew may be so thick that it drips off the leaves onto the ground or other plants underneath. And in some cases, a black, powdery fungus called sooty mold grows on it, causing the plant's leaves to look dirty.
We've written about quite a few of the insects that produce honeydew in our blog, so here is a list of the possible culprits that may be causing the mess this time of year:
The hackberry woolly aphid is a major pest on
You may see leafhoppers in your garden or landscape this time of year as they hop about feeding on a variety of plants. You can distinguish these small, wedge-shaped insects from other pests by their tendency to quickly jump or crawl rapidly sideways when disturbed.
Leafhoppers are sucking insects that insert their mouthparts into plants and suck out plant juices and cell contents. Damage occurs during feeding, which typically results in leaves looking stippled (little white dots), bleached, pale, or brown, and plant shoots may curl and die. You may notice a sticky residue on the plants called honeydew, a waste product from when some species of leafhoppers feed. A fungus called sooty mold may grow on the honeydew, which can be...
It's hot outside, so like a lot of people, you try to park your car under a tree in parking lots and on the street for some shade. 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.
If you examine the tree's leaves, you may see bluish-white masses that are actually...
If you have ants climbing up and down trees and shrubs in your landscape, and your trees and shrubs appear to have a sticky substance covering their leaves, you'll want to watch UC IPM's newest YouTube video, “Using a Sticky Barrier to Prevent Ants on Trees and Shrubs”.
The short video explains that the sticky substance on your leaves is honeydew, a sugary substance excreted by aphids, psyllids and a few other plant pests. Ants harvest this...
Have you ever had an infestation of mealybugs on your houseplants or outside on your landscape plants? You may have wondered, “Where did these insects come from?” Mealybugs are often introduced into landscapes and indoors from plant material brought home on other plants, tools, or pots.
What are Mealybugs?
Mealybugs are small, wingless, oval-shaped insects that congregate in large numbers on plants. They form white, cottony masses and are often confused with other pests that produce waxy coatings like cottony cushion...