Lace bugs are sap-sucking pests that feed on deciduous and evergreen plants during the spring and summer, weakening their host plants. These pests thrive in full sun under dry conditions. Depending on the species, they are about 1/8-inch long and whitish with tan markings. Their most distinctive physical trait is, of course, lace-like front wings. In general, there are two (and up to five) generations per season, especially for some species, when temperatures are above normal.
Lace bugs attack multiple plant species, including azalea, cotoneaster, hawthorn, mountain-laurel, oak, pieris, pyracantha, quince, rhododendron and sycamore.
These chlorophyll-removing insects are known for their piercing-sucking feeding style, similar to spider mites. Signs of infestation include bleached-looking leaves, premature leaf drop, and black, shiny lace bug excrement on the underside of leaves.
Because lace bugs flourish in hot, dry conditions, naturally occurring fungal diseases can reduce populations when host plants are located in cool, shady areas. Monitor sun-loving plants for infestations and, if necessary, apply an appropriate pesticide two to three times from spring through the end of summer. Talk to a certified arborist about soil-injected controls, which can provide season-long protection.