Lace bugs (Stephanitis) are small, around 1/8 inch long, insects of the Tingidae family. The adults have clear, highly ornate, lace-like wings that fold over their roughly rectangular bodies, and the nymphs are oval in shape. Both adults and nymphs are found on the undersides of leaves, along with their cylindrical eggs, which are dark from a protective coating of the females’ excrement.
These bugs damage plants by sucking the sap from the leaf cells. The empty cells give the leaves a
pale, grayish dusty look, similar to the damage from spider mites. Unlike mites, lace bugs also leave their shiny black excrement on the undersides of the leaves, called tar spots.
Lace bugs overwinter as eggs on the lower surface of leaves. Egg hatching time in the spring can vary in Richmond, so we recommend careful monitoring of your plants beginning in early April. It is important to catch an infestation quickly, as lace bugs reproduce rapidly. While these insects do not usually kill a plant, they disfigure some of our favorite garden ornamentals—azaleas, rhododendrons, cotoneasters, and other broad-leaved evergreens.
Once you have identified the presence of lace bugs, treat the plant with an insecticide such as Orthene, following the directions on the label as to frequency of application, being sure to spray the undersides of the leaves where the insects are feeding. For a small infestation, you can try spraying insecticidal soap, again treating the lower leaf surfaces. If you prefer organic controls, Lacewing (Chrysoperla) is a general predator that will hunt and eat lace bugs. Continue to monitor your plants regularly to make sure you have the infestation under control.