Hawthorn Lace Bugs Identification Guide
Corythucha cydoniae
Hawthorn lace bugs are small sap-feeding insects with delicate lace-patterned wings that feed on hawthorn, pyracantha, cotoneaster, and other rosaceous plants. They cause stippling damage to leaves and may enter homes seeking shelter in fall.
Taxonomy
Hawthorn Lace Bugs Coloration
Common color patterns to help identify hawthorn lace bugs
Hawthorn Lace Bugs
Seasonal Activity
When hawthorn lace bugs are most active throughout the year
Where Hawthorn Lace Bugs Are Found
Hover over states to see their names. Green regions indicate where hawthorn lace bugs have been reported.
Hawthorn Lace Bug Identification Guide
Physical Characteristics
Hawthorn lace bugs are small, flat insects about 3 to 4 millimeters long (roughly 1/8 inch). Their wings have a clear, mesh-like pattern that gives them their “lace” name. From above, the wings and body covering look like fine netting or delicate fabric.
Adults are tan to cream colored with brown spots and bands on the wings. One key identifying feature is the straight back edge of the wing crossbar near the tip. The hood that covers the head stands tall, rising more than twice as high as the ridge on the middle body. Small hairs and spines line the outer edges of the wings and body.
The nymphs look very different from the adults. Young nymphs are spiny and dirty brown. As they grow, they become flatter and more oval-shaped. They do not have the lacy wings until they become adults after going through five growth stages.
Common Species
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Hawthorn Lace Bug (Corythucha cydoniae): The main species found across the continental United States, southern Canada, and northern Mexico. You can tell it apart from other lace bugs by the plants it attacks and the unique shape of its hood and wing markings.
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Related Tingidae Species: Several related lace bugs attack different plants. Oak lace bugs feed on oak and beech trees, sycamore lace bugs target plane trees, and azalea lace bugs damage rhododendrons and azaleas. Each species prefers specific host plants.
Hawthorn Lace Bug Behavior and Biology
Hawthorn lace bugs spend winter as adults in sheltered spots near their host plants. They hide in fallen leaves on the ground, bark cracks on trees, grass clumps, mulch, and sometimes gaps in building walls. Unlike some lace bugs that survive winter as eggs, hawthorn lace bugs make it through as adults.
When spring arrives and temperatures warm up, the adults come out and fly to their host plants. They start feeding on the new leaves. Females lay eggs in small groups on the bottom of leaves, usually along the main veins. They coat the eggs with a hard brown coating that protects them. A single female can lay dozens of barrel-shaped, dark brown eggs.
Eggs hatch in one to two weeks, faster in warm weather. The tiny nymphs start feeding right away and stay grouped together on the bottom of leaves. They go through five growth stages before turning into winged adults. The whole process from egg to adult takes about 30 to 40 days in good conditions.
In most of the Mid-Atlantic region, hawthorn lace bugs have three to four generations per year. Numbers grow through the summer, reaching their peak in August and September when several generations are active at once. This is why damage often seems to show up suddenly and get much worse in late summer.
Both nymphs and adults feed by poking their needle-like mouthparts into leaf cells and sucking out the contents. This removes the green color from leaves and creates yellow or white speckles on the top of leaves. Bad infestations leave the bottom of leaves covered with shed skins, black waste spots, and egg clusters. These signs make lace bug damage easy to identify.
Treatment Methods for Hawthorn Lace Bugs
Treating hawthorn lace bugs means protecting your plants and keeping them out of your home in the fall. Since these insects mainly damage landscape plants and not buildings, control focuses on keeping plants healthy and using treatments when needed.
Cultural and Preventive Approaches
Keeping your plants healthy is the first step in lace bug control. Healthy shrubs can handle light feeding damage much better than stressed plants. Water your plants well during dry spells since drought-stressed plants get hurt worse and take longer to recover. Do not over-fertilize, as too much new growth can attract more lace bugs.
Where you plant matters too. Pyracantha, hawthorn, and cotoneaster in full sun tend to get worse lace bug problems than those in partial shade. If you are planting new shrubs, pick spots that get some afternoon shade.
If hawthorn lace bugs are getting into your home in fall, seal them out. Caulk gaps around windows, doors, and pipes. Add door sweeps and fix any torn screens. These steps cut down on the number of bugs that make it inside.
Monitoring and Detection
Check your plants often so you can catch problems early. Starting in late April or early May, look at the bottom of leaves for adults and young nymphs. Watch for black waste spots and early speckled damage. Finding them early gives you the best chance to control them.
Not every lace bug sighting needs treatment. Light damage on healthy plants is often just cosmetic. Focus treatment efforts on plants showing heavy damage or those with a history of severe problems.
Treatment Options
When you need to treat, several methods work well:
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Horticultural oils and insecticidal soaps work well when sprayed on the bottom of leaves where lace bugs feed. These products work best on young nymphs and need to cover all the leaves. You may need to spray again as new generations hatch.
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Systemic treatments poured around the base of plants give longer-lasting protection. The product moves up through the plant and kills lace bugs when they feed. This works well for plants that have problems every year.
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Contact insecticides can reduce numbers but you must spray carefully to reach bugs on the bottom of leaves. Treating early in each generation when nymphs are young works best.
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Targeted applications that focus only on infested plants help keep treatment costs down. Spot treating problem areas rather than blanket spraying an entire landscape is often the most practical approach.
References
Other Lace Bugs
Explore other species in the lace bugs family
Commonly Confused With
Hawthorn Lace Bugs are often mistaken for these similar pests
Where Hawthorn Lace Bugs Are Found
Hover over states to see their names. Green regions indicate where hawthorn lace bugs have been reported.
Common Questions about Hawthorn Lace Bugs
What plants do hawthorn lace bugs feed on?
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Hawthorn lace bugs primarily attack rosaceous plants including hawthorn, pyracantha (firethorn), cotoneaster, and quince. They may also feed on serviceberry, apple, pear, and occasionally oak trees. Both adults and nymphs feed on the undersides of leaves.
Are hawthorn lace bugs harmful to humans?
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No, hawthorn lace bugs do not bite, sting, or transmit diseases to humans. They are strictly plant feeders and pose no health risk to people or pets. They become a nuisance only when they enter homes seeking overwintering shelter in fall.
How can I tell if my plants have hawthorn lace bugs?
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Look for yellow or white stippling on upper leaf surfaces that resembles bleaching. Check leaf undersides for small tan insects with lacy wings, dark spiny nymphs, and shiny black fecal spots. Heavily damaged leaves may turn bronze and drop prematurely.
When are hawthorn lace bugs most active?
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Hawthorn lace bugs are most active from late spring through early fall. Populations build through summer with three to four generations per year in most areas. The heaviest infestations typically occur in late summer when multiple generations overlap.
Why are hawthorn lace bugs entering my house?
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In fall, adult hawthorn lace bugs leave their host plants to find protected overwintering sites. They may gather on sunny exterior walls and enter homes through gaps around windows and doors. They overwinter in bark crevices, leaf litter, or inside structures.
Will hawthorn lace bugs kill my shrubs?
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Hawthorn lace bugs rarely kill healthy, established plants but can cause significant cosmetic damage. Repeated severe infestations stress plants and may reduce flowering. Young or drought-stressed plants are more vulnerable to lasting damage from heavy feeding.
What is the best time to treat for hawthorn lace bugs?
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The most effective time to treat is when nymphs first appear in spring, typically in May. Young nymphs are more vulnerable to control measures than adults. Monitor plants starting in late April and treat when you first notice nymph activity and early damage.
With five years of hands-on experience in the pest control industry, George Schulz is a registered technician with the Virginia Pest Management Association and a proud third-generation professional in a family business that's been protecting homes for over 57 years. He manages and trains a team of service pros while also leading internal research efforts—recently spearheading a deep-dive review of thousands of documents on pest control materials to hand-pick the most kid and pet friendly, most effective solutions tailored specifically for homes in the DC metro area.