Lace Bugs

Lace bugs are not the same thing as lacewings.

Lace bug (USGS Bee Inventory and Monitoring Lab) Public Domain

​Common lacewings (Chrysopidae) are voracious predators, easily recognized by their narrow green or brown bodies and lacy wings. Lacewings have earned the name ‘aphid lions’ by consuming large quantities of aphids, along with small beetles, caterpillars, scale insects, leafhoppers, thrips, mites, and small flies. Lace bugs (Tingidae) are something else entirely.

Green lacewing (John Tann) CC BY 2.0

There are over 2,000 lace bug species and each one is plant-specific. Most lace bugs spend their entire lives in the same area of the same plant, even though they can fly. And they bite! Apparently, they don’t fly very well because sometimes they fall out of their trees and bite the people they land on. While these bites do sting, they are not dangerous.

Lace bug identification

Lace bugs are very small. You could fit up to 8 or 9 lace bugs end-to-end across a dime, though some species are significantly bigger than that. Lace bugs tend to be tan, brown, or black, depending on the species.

Lace bugs get their name because of their diaphanous fore wings and lacy outgrowths on their thorax. They can be broad or narrow but most lace bug bodies are flattened and the heads are often hidden under a hood-like pronotum.

Basil lace bug on lavender (Stemonitis) CC BY-SA 3.0

Damage caused by lace bugs

Lace bugs are host-specific sap suckers. They are most often found on the underside of leaves where they pierce leaf tissue and tap into plant cells to feed on sap. This feeding initially causes small yellow or white spots. Eventually, lace bug feeding leads to leaf silvering or bronzing. It can also provide points of entry for anthracnose.

Heavy infestations can lead to leaf curling, leaf drop, and reduced crop size. These pests frequently feed on young shoots which leads to wilting and twig death. If all that wasn’t bad enough, it ends up that these pests use both the upper and lower decks of their leaves as a toilet, leaving behind black flecks of excrement

Symptoms of cotton lace bug infestation (Scot Nelson) Public Domain

Here are just a few lace bug species you may find in your garden:
​Avocado lace bug (Pseudacysta perseae)—aka camphor lace bug; black or brown bugs that feed on avocado

• Basil lace bug (Cochlochila bullita)—black or brown bugs that feed on basil, rosemary, safflower, and sage
• Cherry lace bug (Corythucha associata)—dark brown bugs that feed on cherry and some plum species
• Eggplant lace bug (Gargaphia solani)—tan or gray bugs that feed on eggplant, tomatoes, potatoes, and salvia

There are also lace bug species that attack azalea, bamboo, banana, cotton, oak, sycamore, and willow, just to name a few.

Lace bug lifecycle

Lace bugs go through an incomplete metamorphosis that takes them through 4 or 5 instars, depending on the species. Generally speaking, wing pads appear in the second or third instar and continue to develop into adulthood. There may be two to five generations of lace bugs each year, depending on the species and environmental conditions. They may overwinter as eggs, nymphs, or adults.

Eggplant lace bug (Judy Gallagher) CC BY 2.0

Oblong lace bug eggs can be yellowish to black. Some species lay their eggs are at an angle, in circular arrangements, on the underside of leaves, similar to whitefly eggs. The only difference is that the eggs are then covered with black, sticky frass (bug poop). Yuck! Other lace bug species insert their eggs into stems and shoots, while some species lay their eggs along the edge, or margin, of nearby leaves or leaf veins. Unlike many other insects, lace bug mothers are protective of their young. When predators appear, Moms fan their wings and approach the threat as only a protective mom can do.

Lace bug management

Small populations of lace bugs are no cause for concern. In fact, their presence attracts many beneficial predators. Simply keep your trees and plants healthy with good drainage, mulch, and proper feeding and irrigation. These pests may overwinter on horsenettle (Solanum carolinense) and common mullein (Verbascum thapsus), so you may want to keep those plants away from your garden.

Assassin bugs, jumping spiders, lacewing larvae, ladybugs, pirate bugs, predaceous mites, predatory thrips, and spined soldier bugs will all help keep lace bug populations under control, so avoid using broad-spectrum pesticides. Severe infestations are best managed with insecticidal soap or narrow-range oil sprays.