Adult Sycamore Lace Bugs

Identifying Adults

• The adult sycamore lace bug is a small insect that measures no more than 1/8 inch long. This insect is brown to black and has an elaborate thorax and forewings that cover its body. The thorax and forewings feature tiny, clear cells that give the bug a lacy or gauzelike appearance. This covering also gives lace bugs a somewhat silvery look.

Feeding Damage

• Both lace bug adults and the immature nymphs use piercing mouth parts to feed on sap from sycamore leaves. The leaf tissue around the feeding sites turns yellow, giving the upper leaf surface a yellow, then brown, stippled appearance. Leaf undersides will host dark specks of excrement and cast-off skins from lace bug nymphs. Premature leaf drop may occur. Lace bug feeding on a sycamore tree is usually not serious but a heavy infestation can reduce a sycamore's growth.

Lace Bug Life Cycle

• The adult lace bug survives through the winter on the sycamore, emerging at about the same time the sycamore's leaves begin to appear. The adult female lace bug lays eggs on a leaf's lower surface. Lace bug nymphs hatch within a few days. The nymphs lack wings, are oval and are smaller than adults. Over about six weeks, the nymphs molt several times, eventually becoming adults. Several generations of lace bugs can occur in a single year, with all life stages possibly present at the same time and feeding together on leaves.

Control

• Sycamore lace bugs have several natural enemies, including lacewings, predaceous mites, minute pirate bugs, spiders, lady beetles and assassin bugs. These beneficials often sufficiently control lace bug numbers. To conserve the numbers of lace bug predators and parasites, don't use broad-spectrum, persistent pesticides in the area. Inspect the sycamore tree foliage regularly, from when the leaves emerge, looking for lace bug activity. On small trees, regularly spraying the foliage with a forceful stream of water can address a minor lace bug infestation.