By Erin Marissa Russell and Matt Gibson
Lace bugs are frequent visitors to the modern garden, and you’ll find them feeding on all kinds of trees, shrubs, and herb plants. Despite how common these pesky insects are and the fact that they consume the plants we humans cultivate in our gardens, they’re not usually a problem for gardeners. That’s because unless their population is really booming in your backyard, lace bugs don’t cause a substantial level of damage to the plants they feed on. Lace bugs are from the species Stephanitis spp., and Corythucha spp.
It’s only when a lace bug infestation is really severe and there are lots and lots of the insects feeding on plants that the damage their dining leaves behind begins to be really noticeable. When there are lots of these insects in the garden, however, they can diminish the beauty of a gardener’s plants. That’s why you may wish to take steps to prevent too many lace bugs from stopping by your garden—or to fight off a lace bug infestation, if one is in progress on your plants.
Plants Susceptible to Lace Bug Damage
There’s a huge number of plants that lace bugs may feed on, but some of the varieties they’re most commonly attracted to in the garden include those listed below.
- Alder (Alnus)
- American Basswood, also called American Linden (Tilia americana)
- Andromeda (Andromeda polifolia)
- Aster (Symphyotrichum)
- Azalea (Rhododendron)
- Balsam and Balsam Poplar (Abies balsamea and Populus balsamifera
- Beech (Fagus)
- Bigtooth Aspen (Populus grandidentata)
- Birch (Betula)
- Black Walnut (Juglans nigra)
- Buckeye (Aesculus)
- Butternut (Juglans cinerea)
- Cherry (Prunus avium)
- Chokecherry also called Bitter-Berry and Virginia Bird Cherry (Prunus virginiana)
- Crabapple (Malus)
- Elm (Ulmus)
- Goldenrod (Solidago)
- Hackberry (Celtis occidentalis)
- Hawthorn also called Hawberry, Quickthorn, May-Tree, Thornapple, and Whitethorn (Crataegus)
- Hazel (Corylus)
- London Plane Tree also called Hybrid Plane Tree (Platanus × acerifolia)
- Oak (Quercus)
- Pincushion Flower (Scabiosa, also called Scabious)
- Quaking Aspen (Populus tremuloides)
- Quince (Cydonia oblonga)
- Scarlet Firethorn (Pyrancantha coccinea)
- Serviceberry (Amelanchier)
- Sycamore (Platanus)
- Willow (Salix)
How to Identify Lace Bugs
Lace bugs can be between one-eighth of an inch and one-third of an inch long depending on which species of lace bug you are dealing with. Lace bugs get their names because of their intricately-designed, semi-transparent outer shells, which have a lace-like appearance. The pest’s bodies and wings, upon very close inspection, have elevated ridges, and look as if they are covered in a thin layer of lace.
At the nymph stage, the bugs are still wingless, quite small, and covered with tiny spines. When they lay their small, oval-shaped eggs, they cover them with a layer of black excrement to protect them. The excrement looks like a lacquer or varnish that coats the surface of the egg pile, and its purpose is to hide the eggs from predators and to make it harder for them to get to the actual eggs beneath the coating.
Lace Bug Damage
Both the nymphs and the adult lace bugs damage infested plants in the same way, by using their sharp, piercing mouthparts to pierce the underside of leaves, then feed on the plant by sucking out its juices. Once the nymphs molt, their skin shell castoff stays stuck to the lower surface of the leaves, a clear sign of their presence.
Damage will be noticed on the upper sides of leaves of the affected plant in the form of multiple, tiny, pale wounds that may be separated or merged together as one larger spot on the leaf surface. This effect of this damage on tree foliage is known as strippling. You can distinguish the damage caused by lace bugs from other pests that produce similar problems (like thrips) due to the large amount of dark excrement that lace bugs leave behind on the surface of lower leaves.
How to Prevent Lace Bugs
Even better than being able to say you’ve successfully battled an influx of lace bugs is taking the measures that allow you to skip the battle completely. Gardeners can use these techniques to keep lace bugs from ever making a home on their plants in the first place.
- Go for resistant varieties to avoid needing to worry about lace bugs in the garden. There are plenty of plant varieties available on the market that are resistant to infestation by lace bugs. When you choose to plant a resistant variety, you don’t have to worry about staying vigilant against the signs of lace bug infestation in the future, and you also won’t have to deal with lace bugs in your garden.
- Inspect plants on a consistent basis so you spot signs of lace bugs or their damage quickly. One of the best ways to prevent having to roll out lots of treatments against a full-fledged lace bug infestation is performing regular plan inspections so that you will notice the signs that indicate lace bugs are making a home of your plants as quickly as possible.
How to Treat a Lace Bug Infestation
It’s not necessary to treat a lace bug invasion in your garden just because one exists. As we mentioned earlier, often lace bug infestations don’t do more than cosmetic damage to the plants they inhabit. It takes a large number of lace bugs on a plant to cause a problem that a gardener needs to address with treatments like those below.
- Call in reinforcements with natural predators. There are plenty of insects that are natural predators of the lace bug that you can either purchase or attract to the garden to help stop an infestation. These include green lacewings, lady beetles, mirid plant bugs, minute pirate bugs, mymarid wasps, and spiders. You can learn more about attracting beneficial insects like these in this article.
- Use a spray of water to knock lace bugs off vulnerable plants. This treatment doesn’t only work against lace bugs; it’s good against aphids, whiteflies, and other small insects as well. Simply aim a high-pressure stream of water from your garden hose at the affected plants, and you can knock the lace bugs off of the plants they’re infesting. You may need to repeat this treatment several times in order for it to be effective. This treatment works best when you don’t see too many lace bugs on your trees and the damage is not yet noticeable.
- Rely on insecticidal soaps and horticultural oils to keep lace bugs at bay. Treatments of insecticidal soap or horticultural oil can be quite effective against lace bugs. However, you may need to use these treatments repeatedly to see an effect.
If none of the environmental and cultural controls we’ve outlined here work in your garden against lace bugs, you may choose to use insecticides, as there are many that are effective against lace bugs.
However, most infestations of lace bugs do not require treatment at all since damage tends to be cosmetic and is not normally noticeable unless the lace bug population is really booming. That’s why most gardeners will find that the natural remedies we’ve discussed in this article meet their needs and will stave off the lace bug problems that plague their gardens.
Learn More About Lace Bugs